0001564590-21-009436 | 10-K | XBRL Viewer

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Reconciliations of Statutory U.S. Federal Income Tax Rates to Our Effective Tax Rate for Continuing Operations

Reconciliations of the statutory U.S. federal income tax rates to our effective tax rate for continuing operations follow:

	Years Ended December 31,
	2020			2019			2018
Statutory rate		21.0	%		21.0	%		21.0	%
State tax, net of federal benefit		1.6			1.4			3.9
Other, net		—			(.5	)		.3
Effective tax rate		22.6	%		21.9	%		25.2	%

Components of Provision for Income Tax Expense (Benefit)

Income tax expense consists of:

	December 31,
(Dollars in millions)	2020			2019		2018
Current provision/(benefit):
Federal	$	98		$	78	$	71
State		14			11		13
Foreign		(1	)		—		3
Total current provision/(benefit)		111			89		87
Deferred provision/(benefit):
Federal		12			73		33
State		(3	)		3		13
Foreign		—			1		—
Total deferred provision/(benefit)		9			77		46
Provision for income tax expense/(benefit)	$	120		$	166	$	133

Schedule of Deferred Tax Assets and Liabilities

The tax effect of temporary differences that give rise to deferred tax assets and liabilities include the following:

	December 31,
(Dollars in millions)	2020		2019
Deferred tax assets:
Loan reserves	$	414	$	257
Market value adjustments on education loans, investments and derivatives		64		—
Education loan premiums and discounts, net		41		44
Operating loss and credit carryovers		14		17
Accrued expenses not currently deductible		22		16
Stock-based compensation plans		6		10
Other		22		21
Total deferred tax assets		583		365
Deferred tax liabilities:
Acquired intangible assets		16		17
Market value adjustments on education loans, investments and derivatives		—		13
Original issue discount on borrowings		11		10
Other		16		18
Total deferred tax liabilities		43		58
Net deferred tax assets	$	540	$	307

Summary of Operating Loss and Credit Carryovers

The operating loss and credit carryovers consist of:

	December 31, 2020
(Dollars in millions)	Gross		Tax-Effected		Expiration	Corresponding Valuation Allowance⁽¹⁾		Operating Loss and Credit Carryovers
Federal operating loss carryovers	$	53	$	11	Begins in 2031	$	—	$	11
State operating loss carryovers		505		36	Begins in 2021		33		3
State IRC § 163(j) disallowed interest expense carryovers		1,907		29	Indefinite		29		—
Federal and State capital loss carryovers		10		2	Begins in 2021		2		—
			$	78		$	64	$	14

⁽¹⁾

The valuation allowance attributable to deferred tax assets for federal and state net operating loss carryovers, and state IRC § 163(j) disallowed interest expense carryovers, are amounts that management believes more likely than not will expire prior to being realized.

Summary of Changes in Unrecognized Tax Benefits

The following table summarizes changes in unrecognized tax benefits:

	December 31,
(Dollars in millions)	2020			2019			2018
Unrecognized tax benefits at beginning of year	$	53.6		$	65.7		$	57.4
Increases resulting from tax positions taken during a prior period		7.6			4.0			8.0
Decreases resulting from tax positions taken during a prior period		—			(3.8	)		(.3	)
Increases resulting from tax positions taken during the current period		3.5			1.9			3.8
Decreases related to settlements with taxing authorities		(.2	)		(11.1	)		(1.4	)
Increases related to settlements with taxing authorities		—			—			—
Reductions related to the lapse of statute of limitations		(6.6	)		(3.1	)		(1.8	)
Unrecognized tax benefits at end of year⁽¹⁾	$	57.9		$	53.6		$	65.7

⁽¹⁾ Included in the $57.9 million of gross unrecognized tax benefits at December 31, 2020 are $45.7 million of unrecognized tax benefits that, if recognized, would favorably impact the effective tax rate.

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Assets
Loans, net	$ 79,363	$ 86,820
Investments
Held-to-maturity	15	19
Other	270	192
Total investments	285	211
Cash and cash equivalents	1,183	1,233
Restricted cash and cash equivalents	2,354	2,548
Goodwill and acquired intangible assets, net	735	757
Other assets	3,492	3,334
Total assets	87,412	94,903
Liabilities
Short-term borrowings	6,613	8,483
Long-term borrowings	77,332	81,715
Other liabilities	1,020	1,356
Total liabilities	84,965	91,554
Commitments and contingencies
Equity
Common stock, par value $0.01 per share; 1.125 billion shares authorized: 454 million and 451 million shares issued, respectively	4	4
Additional paid-in capital	3,226	3,198
Accumulated other comprehensive loss (net of tax benefit of $90 and $30, respectively)	(274)	(91)
Retained earnings	3,331	3,664
Total Navient Corporation stockholders’ equity before treasury stock	6,287	6,775
Less: Common stock held in treasury at cost: 267 million and 236 million shares, respectively	(3,854)	(3,439)
Total Navient Corporation stockholders’ equity	2,433	3,336
Noncontrolling interest	14	13
Total equity	2,447	3,349
Total liabilities and equity	87,412	94,903
Assets and Liabilities of Consolidated Variable Interest Entities [Member]
Assets
Loans, net	76,726	83,864
Investments
Total assets	80,468	87,459
Investments
Restricted cash	2,322	2,506
Other assets, net	1,420	1,089
Liabilities
Short-term borrowings	5,595	7,089
Long-term borrowings	68,900	72,856
Net assets of consolidated variable interest entities	5,973	7,514
FFELP Loans [Member]
Assets
Loans, net	58,284	64,575
FFELP Loans [Member] \| Assets and Liabilities of Consolidated Variable Interest Entities [Member]
Assets
Loans, net	58,068	64,255
Private Education Loans [Member]
Assets
Loans, net	21,079	22,245
Private Education Loans [Member] \| Assets and Liabilities of Consolidated Variable Interest Entities [Member]
Assets
Loans, net	$ 18,658	$ 19,609

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 412	$ 597	$ 395
Net changes in cash flow hedges, net of taxes	(183)	(204)	39
Total comprehensive income	$ 229	$ 393	$ 434

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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+ Details

Other Assets - Schedule of Other Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Accrued interest receivable	$ 1,933	$ 1,952
Benefit and insurance-related investments	469	459
Income tax asset, net	454	258
Derivatives at fair value	307	212
Fixed assets, net	116	135
Accounts receivable	118	119
Other	95	199
Total	$ 3,492	$ 3,334

Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities
Net income	$ 412	$ 597	$ 395
Adjustments to reconcile net income to net cash provided by operating activities:
(Gains) on sale of education loans		(16)
(Gains) losses on debt repurchases	6	(45)	(19)
Goodwill and acquired intangible asset impairment and amortization expense	22	30	47
Stock-based compensation expense	18	25	25
Mark-to-market (gains)/losses on derivative and hedging activities, net	340	130	37
Provisions for loan losses	155	258	370
Decrease (increase) in accrued interest receivable	22	78	(125)
(Decrease) increase in accrued interest payable	(113)	(96)	58
Decrease in other assets	177	191	321
(Decrease) increase in other liabilities	(52)	(133)	31
Total adjustments	575	422	745
Total net cash provided by operating activities	987	1,019	1,140
Investing activities
Education loans acquired	(4,641)	(5,411)	(3,652)
Principal payments on education loans	11,179	12,472	13,973
Proceeds from sales of education loans		408
Other investing activities, net	(90)	9	(76)
Proceeds from sales and maturities of other securities		7	115
Total net cash provided by investing activities	6,448	7,485	10,360
Financing activities
Borrowings collateralized by loans in trust - issued	7,959	7,919	9,006
Borrowings collateralized by loans in trust - repaid	(11,858)	(14,271)	(14,057)
Long-term unsecured notes issued	682		495
Long-term unsecured notes repaid	(1,832)	(1,950)	(2,947)
Other financing activities, net	(192)	(189)	(162)
Common stock repurchased	(400)	(440)	(220)
Common dividends paid	(123)	(147)	(166)
Total net cash used in financing activities	(7,679)	(9,985)	(10,884)
Net (decrease) increase in cash, cash equivalents, restricted cash and restricted cash equivalents	(244)	(1,481)	616
Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of period	3,781	5,262	4,646
Cash, cash equivalents, restricted cash and restricted cash equivalents at end of period	3,537	3,781	5,262
Cash disbursements made (refunds received) for:
Interest	2,059	3,479	3,460
Income taxes paid	74	93	57
Income taxes received		(4)	(6)
Non-cash activities
Investing activity - Held-to-maturity asset backed securities retained related to sales of education loans		22
Operating activity - Servicing assets recognized upon sales of education loans		3
Reconciliation of the Consolidated Statements of Cash Flows to the Consolidated Balance Sheets:
Cash and cash equivalents	1,183	1,233	1,286
Restricted cash and restricted cash equivalents	2,354	2,548	3,976
Cash, cash equivalents, restricted cash and restricted cash equivalents at end of period	3,537	3,781	5,262
Asset-backed Securities, Securitized Loans and Receivables [Member]
Financing activities
Asset-backed commercial paper conduits, net	$ (1,915)	$ (907)	$ (2,833)

Derivative Financial Instruments - Gross Positions without Impact of Master Netting Agreements (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Derivatives Fair Value [Line Items]
Derivative assets	$ 357	$ 230
Derivative values with impact of master netting agreements (as carried on balance sheet), Assets	307	212
Cash collateral (held) pledged, Assets	(336)	(337)
Derivative liabilities	(533)	(664)
Cash collateral (held) pledged, Liabilities	234	155
Other Assets [Member]
Derivatives Fair Value [Line Items]
Derivative assets	357	230
Impact of master netting agreements, Assets	(50)	(18)
Derivative values with impact of master netting agreements (as carried on balance sheet), Assets	307	212
Cash collateral (held) pledged, Assets	(336)	(337)
Net position, Assets	(29)	(125)
Other Liabilities [Member]
Derivatives Fair Value [Line Items]
Derivative liabilities	(533)	(664)
Impact of master netting agreements, Liabilities	50	18
Derivative values with impact of master netting agreements (as carried on balance sheet), Liabilities	(483)	(646)
Cash collateral (held) pledged, Liabilities	234	155
Net position, Liabilities	$ (249)	$ (491)

Earnings (Loss) per Common Share - Schedule of Earnings (Loss) per Common Share (Parenthetical) (Detail) - shares shares in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities not included in the computation of diluted earnings per share	2	4	6

Allowance for Loan Losses - Age Analysis of Past Due Loans Delinquencies (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans in repayment and percentage of each status:
Total Loans		$ 88,013	$ 96,014
Loan allowance for losses	$ (1,377)	(1,112)	(1,286)	$ (1,367)
Loans, net	79,363	86,820
FFELP Loans [Member]
Loans in repayment and percentage of each status:
Loans unamortized premium (discount)	497
Total Loans	58,572	64,094	71,730
Loan allowance for losses	(288)	(64)	$ (76)	$ (60)
Loans, net	58,284	64,575
Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Total Loans, gross	8,431	9,270
Loans unamortized premium (discount)		(203)
Total Loans	8,431	9,067
Loans receivable for partially charged-off loans		347
Loan allowance for losses	(929)	(941)
Loans, net	$ 7,502	$ 8,473
Dimensions of concentration risk	100.00%	100.00%
Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Total Loans, gross	$ 13,737	$ 14,052
Loans unamortized premium (discount)		(414)
Total Loans	13,737	13,638
Loans receivable for partially charged-off loans		241
Loan allowance for losses	(160)	(107)
Loans, net	$ 13,577	$ 13,772
Dimensions of concentration risk	100.00%	100.00%
Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Total Loans, gross	$ 58,572	$ 64,094
Loans unamortized premium (discount)		545
Total Loans	58,572	64,639
Loan allowance for losses	(288)	(64)
Loans, net	$ 58,284	$ 64,575
Dimensions of concentration risk	100.00%	100.00%
Credit Concentration Risk [Member] \| Financing Receivables, 31 to 60 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent, percentage	2.50%	3.50%
Credit Concentration Risk [Member] \| Financing Receivables, 31 to 60 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent, percentage	0.20%	0.40%
Credit Concentration Risk [Member] \| Financing Receivables, 31 to 60 Days Past Due [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Loans delinquent, percentage	2.90%	3.90%
Credit Concentration Risk [Member] \| Financing Receivables, 61 to 90 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent, percentage	1.50%	2.30%
Credit Concentration Risk [Member] \| Financing Receivables, 61 to 90 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent, percentage	0.10%	0.20%
Credit Concentration Risk [Member] \| Financing Receivables, 61 to 90 Days Past Due [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Loans delinquent, percentage	1.70%	2.00%
Credit Concentration Risk [Member] \| Financing Receivables, 90 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent, percentage	2.60%	4.70%
Credit Concentration Risk [Member] \| Financing Receivables, 90 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent, percentage	0.10%	0.30%
Credit Concentration Risk [Member] \| Financing Receivables, 90 Days Past Due [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Loans delinquent, percentage	4.60%	5.80%
Credit Concentration Risk [Member] \| Financing Receivables, Current [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	93.40%	89.50%
Credit Concentration Risk [Member] \| Financing Receivables, Current [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	99.60%	99.10%
Credit Concentration Risk [Member] \| Financing Receivables, Current [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	90.80%	88.30%
Credit Concentration Risk [Member] \| Financing Receivables, Loans In Repayment [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	88.30%	91.10%
Credit Concentration Risk [Member] \| Financing Receivables, Loans In Repayment [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	97.50%	97.10%
Credit Concentration Risk [Member] \| Financing Receivables, Loans In Repayment [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	82.00%	83.50%
Credit Concentration Risk [Member] \| Financing Receivables, Delinquent Loans in Repayment [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	6.60%	10.50%
Credit Concentration Risk [Member] \| Financing Receivables, Delinquent Loans in Repayment [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	0.40%	0.90%
Credit Concentration Risk [Member] \| Financing Receivables, Delinquent Loans in Repayment [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	9.20%	11.70%
Credit Concentration Risk [Member] \| Financing Receivables, Forbearance, Loans In Repayment [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	8.60%	5.40%
Credit Concentration Risk [Member] \| Financing Receivables, Forbearance, Loans In Repayment [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	1.00%	0.90%
Credit Concentration Risk [Member] \| Financing Receivables, Forbearance, Loans In Repayment [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Dimensions of concentration risk	13.80%	12.20%
School/Grace/Deferment [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Total Loans, gross	$ 280	$ 349
School/Grace/Deferment [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Total Loans, gross	203	280
School/Grace/Deferment [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Total Loans, gross	2,791	3,114
Forbearance [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Total Loans, gross	703	479
Forbearance [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Total Loans, gross	141	125
Forbearance [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Total Loans, gross	7,725	7,442
Repayment [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Loans current	6,952	7,557
Total Loans, gross	7,448	8,442
Repayment [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Loans current	13,335	13,526
Total Loans, gross	13,393	13,647
Repayment [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Loans current	43,623	47,255
Total Loans, gross	48,056	53,538
Repayment [Member] \| Credit Concentration Risk [Member] \| Financing Receivables, 31 to 60 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent	185	296
Repayment [Member] \| Credit Concentration Risk [Member] \| Financing Receivables, 31 to 60 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent	26	53
Repayment [Member] \| Credit Concentration Risk [Member] \| Financing Receivables, 31 to 60 Days Past Due [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Loans delinquent	1,374	2,094
Repayment [Member] \| Credit Concentration Risk [Member] \| Financing Receivables, 61 to 90 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent	114	191
Repayment [Member] \| Credit Concentration Risk [Member] \| Financing Receivables, 61 to 90 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent	12	27
Repayment [Member] \| Credit Concentration Risk [Member] \| Financing Receivables, 61 to 90 Days Past Due [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Loans delinquent	836	1,082
Repayment [Member] \| Credit Concentration Risk [Member] \| Financing Receivables, 90 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent	197	398
Repayment [Member] \| Credit Concentration Risk [Member] \| Financing Receivables, 90 Days Past Due [Member] \| Accounts Receivable [Member] \| Private Education Loans - Non-TDRs [Member]
Loans in repayment and percentage of each status:
Loans delinquent	20	41
Repayment [Member] \| Credit Concentration Risk [Member] \| Financing Receivables, 90 Days Past Due [Member] \| Accounts Receivable [Member] \| FFELP Loans [Member]
Loans in repayment and percentage of each status:
Loans delinquent	$ 2,223	$ 3,107

Derivative Financial Instruments

12 Months Ended

Dec. 31, 2020

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Derivative Financial Instruments

7. Derivative Financial Instruments

Risk Management Strategy

We maintain an overall interest rate risk management strategy that incorporates the use of derivative instruments to minimize the economic effect of interest rate changes. Our goal is to manage interest rate sensitivity by modifying the repricing frequency and underlying index characteristics of certain balance sheet assets and liabilities so the net interest margin is not, on a material basis, adversely affected by movements in interest rates. We do not use derivative instruments to hedge credit risk. As a result of interest rate fluctuations, hedged assets and liabilities will appreciate or depreciate in market value. Income or loss on the derivative instruments that are linked to the hedged assets and liabilities will generally offset the effect of this unrealized appreciation or depreciation for the period the item is being hedged. We view this strategy as a prudent management of interest rate sensitivity. In addition, we utilize derivative contracts to minimize the economic impact of changes in foreign currency exchange rates on certain debt obligations that are denominated in foreign currencies. As foreign currency exchange rates fluctuate, these liabilities will appreciate and depreciate in value. These fluctuations, to the extent the hedge relationship is effective, are offset by changes in the value of the cross-currency interest rate swaps executed to hedge these instruments. Management believes certain derivative transactions entered into as hedges, primarily Floor Income Contracts, basis swaps and, at times, certain other LIBOR swaps, are economically effective; however, those transactions do not qualify for hedge accounting under GAAP and thus may adversely impact earnings.

Although we use derivatives to minimize the risk of interest rate and foreign currency changes, the use of derivatives does expose us to both market and credit risk. Market risk is the chance of financial loss resulting from changes in interest rates, foreign exchange rates and market liquidity. Credit risk is the risk that a counterparty will not perform its obligations under a contract and it is limited to the loss of the fair value gain in a derivative that the counterparty owes us. When the fair value of a derivative contract is negative, we owe the counterparty and, therefore, have no credit risk exposure to the counterparty; however, the counterparty has exposure to us. We minimize the credit risk in derivative instruments by entering into transactions with highly rated counterparties that are reviewed regularly by our Credit Department. We also maintain a policy of requiring that all derivative contracts be governed by an International Swaps and Derivative Association Master Agreement. Depending on the nature of the derivative transaction, bilateral collateral arrangements related to Navient Corporation contracts generally are required as well. When we have more than one outstanding derivative transaction with the counterparty, and there exists legally enforceable netting provisions with the counterparty (i.e., a legal right to offset receivable and payable derivative contracts), the “net” mark-to-market exposure, less collateral the counterparty has posted to us, represents exposure with the counterparty. When there is a net negative exposure, we consider our exposure to the counterparty to be zero. At December 31, 2020 and 2019, we had a net positive exposure (derivative gain positions to us less collateral which has been posted by counterparties to us) related to Navient Corporation derivatives of $13 million and $12 million, respectively.

7. Derivative Financial Instruments (Continued)

Our on-balance sheet securitization trusts have $3.6 billion of Euro and British Pound Sterling denominated bonds outstanding as of December 31, 2020. To convert these non-U.S. dollar denominated bonds into U.S. dollar liabilities, the trusts have entered into foreign-currency swaps with highly rated counterparties. In addition, the trusts have entered into $2.4 billion notional of interest rates swaps which are primarily used to convert Prime received on securitized education loans to LIBOR paid on the bonds. Our securitization trusts with swaps have ISDA documentation with protections against counterparty risk. The collateral calculations contemplated in the ISDA documentation of our securitization trusts require collateral based on the fair value of the derivative which may be adjusted for additional collateral based on rating agency criteria requirements considered within the collateral agreement. The trusts are not required to post collateral to the counterparties. At December 31, 2020 and 2019, the net positive exposure on swaps in securitization trusts was $28 million and $0, respectively.

The table below highlights credit exposure related to our derivative counterparties at December 31, 2020.

(Dollars in millions)	Corporate Contracts			Securitization Trust Contracts
Exposure, net of collateral	$	13		$	28
Percent of exposure to counterparties with credit ratings below S&P AA- or Moody’s Aa3		100	%		—	%
Percent of exposure to counterparties with credit ratings below S&P A- or Moody’s A3		—	%		—	%

7. Derivative Financial Instruments (Continued)

Summary of Derivative Financial Statement Impact

The following tables summarize the fair values and notional amounts of all derivative instruments and their impact on net income and other comprehensive income.

Impact of Derivatives on Balance Sheet

		Cash Flow				Fair Value⁽⁴⁾						Trading						Total
(Dollars in millions)	Hedged Risk Exposure	Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2020			Dec. 31, 2019			Dec. 31, 2020			Dec. 31, 2019			Dec. 31, 2020			Dec. 31, 2019
Fair Values⁽¹⁾
Derivative Assets:
Interest rate swaps	Interest rate	$	—	$	—	$	323		$	226		$	6		$	4		$	329		$	230
Cross-currency interest rate swaps	Foreign currency and interest rate		—		—		28			—			—			—			28			—
Total derivative assets⁽²⁾			—		—		351			226			6			4			357			230
Derivative Liabilities:
Interest rate swaps	Interest rate		—		—		—			—			(14	)		(20	)		(14	)		(20	)
Floor Income Contracts	Interest rate		—		—		—			—			(197	)		(68	)		(197	)		(68	)
Cross-currency interest rate swaps	Foreign currency and interest rate		—		—		(322	)		(575	)		—			—			(322	)		(575	)
Other⁽³⁾	Interest rate		—		—		—			—			—			(1	)		—			(1	)
Total derivative liabilities⁽²⁾			—		—		(322	)		(575	)		(211	)		(89	)		(533	)		(664	)
Net total derivatives		$	—	$	—	$	29		$	(349	)	$	(205	)	$	(85	)	$	(176	)	$	(434	)

⁽¹⁾

Fair values reported are exclusive of collateral held and pledged and accrued interest. Assets and liabilities are presented without consideration of master netting agreements. Derivatives are carried on the balance sheet based on net position by counterparty under master netting agreements and classified in other assets or other liabilities depending on whether in a net positive or negative position.

⁽²⁾	The following table reconciles gross positions without the impact of master netting agreements to the balance sheet classification:

	Other Assets						Other Liabilities
(Dollar in millions)	December 31, 2020			December 31, 2019			December 31, 2020			December 31, 2019
Gross position	$	357		$	230		$	(533	)	$	(664	)
Impact of master netting agreements		(50	)		(18	)		50			18
Derivative values with impact of master netting agreements (as carried on balance sheet)		307			212			(483	)		(646	)
Cash collateral (held) pledged		(336	)		(337	)		234			155
Net position	$	(29	)	$	(125	)	$	(249	)	$	(491	)

⁽³⁾	^{“Other” includes derivatives related to our Total Return Swap Facility.}

⁽⁴⁾	^{The following table shows the carrying value of liabilities in fair value hedges and the related fair value hedging adjustments to these liabilities:}

	As of December 31, 2020				As of December 31, 2019
(Dollar in millions)	Carrying Value		Hedge Basis Adjustments		Carrying Value		Hedge Basis Adjustments
Short-term borrowings	$	631	$	4	$	1,001	$	4
Long-term borrowings	$	11,017	$	541	$	11,488	$	(58	)

7. Derivative Financial Instruments (Continued)

The above fair values include adjustments when necessary for counterparty credit risk for both when we are exposed to the counterparty, net of collateral postings, and when the counterparty is exposed to us, net of collateral postings. The net adjustments decreased the asset position at December 31, 2020 and December 31, 2019 by $8 million and $11 million, respectively. In addition, the above fair values reflect adjustments for illiquid derivatives as indicated by a wide bid/ask spread in the interest rate indices to which the derivatives are indexed. These adjustments decreased the overall net asset positions at December 31, 2020 and December 31, 2019 by $5 million and $12 million, respectively.

	Cash Flow				Fair Value				Trading				Total
(Dollars in billions)	Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2020		Dec. 31, 2019
Notional Values:
Interest rate swaps	$	16.7	$	19.1	$	7.5	$	8.6	$	26.8	$	51.5	$	51.0	$	79.2
Floor Income Contracts		—		—		—		—		17.0		21.2		17.0		21.2
Cross-currency interest rate swaps		—		—		3.7		4.0		—		—		3.7		4.0
Total derivatives	$	16.7	$	19.1	$	11.2	$	12.6	$	43.8	$	72.7	$	71.7	$	104.4

Mark-to-Market Impact of Derivatives on Statements of Income

	Total Gains (Losses)
	Years Ended December 31,
(Dollars in millions)	2020			2019			2018
Fair Value Hedges⁽²⁾:
Interest Rate Swaps
Gains (losses) recognized in net income on derivatives	$	301		$	281		$	(137	)
Gains (losses) recognized in net income on hedged items		(327	)		(299	)		162
Net fair value hedge ineffectiveness gains (losses)		(26	)		(18	)		25
Cross currency interest rate swaps
Gains (losses) recognized in net income on derivatives		281			57			(311	)
Gains (losses) recognized in net income on hedged items		(272	)		(18	)		210
Net fair value hedge ineffectiveness gains (losses)		9			39			(101	)
Total fair value hedges⁽¹⁾⁽²⁾		(17	)		21			(76	)
Cash Flow Hedges:
Total cash flow hedges⁽²⁾		—			—			—
Trading
Interest rate swaps		(47	)		44			22
Floor income contracts		(209	)		(22	)		15
Cross currency interest rate swaps		—			(2	)		(3	)
Other		—			2			4
Total trading derivatives⁽³⁾		(256	)		22			38
Mark-to-market gains (losses) recognized	$	(273	)	$	43		$	(38	)

⁽¹⁾	Recorded in interest expense in the consolidated statements of income for 2020 and 2019 with the adoption of ASU No. 2017-12. Recorded in “gains (losses) on derivatives and hedging activities, net” in the consolidated statements of income for 2018.

⁽²⁾	The accrued interest income (expense) on fair value hedges and cash flow hedges is recorded in interest expense and is excluded from this table.

⁽³⁾	Recorded in “gains (losses) on derivative and hedging activities, net” in the consolidated statements of income.

7. Derivative Financial Instruments (Continued)

Impact of Derivatives on Other Comprehensive Income (Equity)

	Years Ended December 31,
(Dollars in millions)	2020			2019			2018
Total gains (losses) on cash flow hedges	$	(233	)	$	(165	)	$	50
Reclassification adjustments for derivative (gains) losses included in net income (interest expense)⁽¹⁾		50			(39	)		(11	)
Net changes in cash flow hedges, net of tax	$	(183	)	$	(204	)	$	39

⁽¹⁾

Includes net settlement income/expense.

Collateral

The following table details collateral held and pledged related to derivative exposure between us and our derivative counterparties.

(Dollars in millions)	December 31, 2020		December 31, 2019
Collateral held:
Cash (obligation to return cash collateral is recorded in short-term borrowings)	$	336	$	337
Securities at fair value — corporate derivatives (not recorded in financial statements)⁽¹⁾		—		—
Securities at fair value — on-balance sheet securitization derivatives (not recorded in financial statements)⁽²⁾		78		69
Total collateral held	$	414	$	406
Derivative asset at fair value including accrued interest	$	351	$	282
Collateral pledged to others:
Cash (right to receive return of cash collateral is recorded in investments)	$	234	$	155
Total collateral pledged	$	234	$	155
Derivative liability at fair value including accrued interest and premium receivable	$	504	$	658

⁽¹⁾	The Company has the ability to sell or re-pledge securities it holds as collateral.

⁽²⁾	The trusts do not have the ability to sell or re-pledge securities they hold as collateral.

Our corporate derivatives contain credit contingent features. At our current unsecured credit rating, we have fully collateralized our corporate derivative liability position (including accrued interest and net of premiums receivable) of $164 million with our counterparties. Downgrades in our unsecured credit rating would not result in any additional collateral requirements. Trust related derivatives do not contain credit contingent features related to our or the trusts’ credit ratings.

Derivative Financial Instruments - Credit Exposure Related Counterparties (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($)
Corporate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Exposure, net of collateral	$ 13
Percent of exposure to counterparties with credit ratings below S&P AA- or Moody’s Aa3	100.00%
Securitization Trust Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Exposure, net of collateral	$ 28

Fair Value Measurements - Fair Values of Financial Assets and Liabilities, Including Derivative Financial Instruments (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and investments	$ 3,822
Loans, Carrying Value	79,363	$ 86,820
Total earning assets, Carrying Value	83,185	90,812
Short-term borrowings, Carrying Value	6,613	8,483
Long-term borrowings, Carrying Value	77,332	81,715
Total	83,945	90,198
Total earning assets, Fair Value	85,401	91,454
Short-term borrowings, Fair Value	6,626	8,498
Long-term borrowings, Fair Value	76,719	81,317
Total interest-bearing liabilities, Fair Value	83,345	89,815
FFELP Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans, Carrying Value	58,284	64,575
Loans receivable, Fair Value	59,117	64,478
Floor Income Contracts [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative financial instruments, Carrying Value	(197)	(68)
Derivative financial instruments, Fair Value	(197)	(68)
Interest Rate Swaps [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative financial instruments, Carrying Value	315	210
Derivative financial instruments, Fair Value	315	210
Cross-Currency Interest Rate Swaps [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative financial instruments, Carrying Value	(294)	(575)
Derivative financial instruments, Fair Value	(294)	(575)
Other [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative financial instruments, Carrying Value		(1)
Derivative financial instruments, Fair Value		(1)
Private Education Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans, Carrying Value	21,079	22,245
Loans receivable, Fair Value	22,462	22,984
Difference [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total earning assets, Fair Value	2,216	642
Short-term borrowings, Fair Value	(13)	(15)
Long-term borrowings, Fair Value	613	398
Total interest-bearing liabilities, Fair Value	600	383
Excess of net asset fair value over carrying value	2,816	1,025
Difference [Member] \| FFELP Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans receivable, Fair Value	833	(97)
Difference [Member] \| Private Education Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans receivable, Fair Value	1,383	739
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and investments	3,822	3,992
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and investments	$ 3,822	$ 3,992

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Loan reserves	$ 414	$ 257
Market value adjustments on education loans, investments and derivatives	64
Education loan premiums and discounts, net	41	44
Operating loss and credit carryovers	14	17
Accrued expenses not currently deductible	22	16
Stock-based compensation plans	6	10
Other	22	21
Total deferred tax assets	583	365
Deferred tax liabilities:
Acquired intangible assets	16	17
Market value adjustments on education loans, investments and derivatives		13
Original issue discount on borrowings	11	10
Other	16	18
Total deferred tax liabilities	43	58
Net deferred tax assets	$ 540	$ 307

Fair Value Measurements - Change in Balance Sheet Carrying Value Associated with Level 3 Financial Instruments Carried at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance, beginning of period	$ (593)	$ (664)	$ (381)
Total gains/(losses):
Included in earnings	239	(50)	(414)
Included in other comprehensive income	0	0	0
Settlements	52	121	131
Transfers in and/or out of level 3	0	0	0
Balance, end of period	(302)	(593)	(664)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date	279	70	(257)
Interest Rate Swaps [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance, beginning of period	(17)	(27)	(41)
Total gains/(losses):
Included in earnings	8	8	11
Included in other comprehensive income	0	0	0
Settlements	1	2	3
Transfers in and/or out of level 3	0	0	0
Balance, end of period	(8)	(17)	(27)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date	5	9	13
Cross-Currency Interest Rate Swaps [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance, beginning of period	(575)	(633)	(322)
Total gains/(losses):
Included in earnings	231	(60)	(433)
Included in other comprehensive income	0	0	0
Settlements	50	118	122
Transfers in and/or out of level 3	0	0	0
Balance, end of period	(294)	(575)	(633)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date	273	58	(284)
Other [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance, beginning of period	(1)	(4)	(18)
Total gains/(losses):
Included in earnings	0	2	8
Included in other comprehensive income	0	0	0
Settlements	1	1	6
Transfers in and/or out of level 3	0	0	0
Balance, end of period	0	(1)	(4)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date	$ 1	$ 3	$ 14

Allowance for Loan Losses - Private Education Loan Portfolio Stratified by Key Credit Quality Indicators (Parenthetical) (Detail) - With Cosigner [Member]	Dec. 31, 2020	Dec. 31, 2019
Accounts Notes And Loans Receivable [Line Items]
Total Private Education Loan Credit Quality Indicators, Excluding Refinance Loans, Percent	65.00%
TDR [Member]
Accounts Notes And Loans Receivable [Line Items]
Total Private Education Loan Credit Quality Indicators, Excluding Refinance Loans, Percent		63.00%
Private Education Loans - Non-TDRs [Member]
Accounts Notes And Loans Receivable [Line Items]
Total Private Education Loan Credit Quality Indicators, Excluding Refinance Loans, Percent		67.00%

Derivative Financial Instruments - Derivative Notional Values (Detail) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Total Derivative Notional Values	$ 71,700,000,000	$ 104,400,000,000
Designated as Hedging Instrument [Member] \| Cash Flow [Member]
Derivative [Line Items]
Total Derivative Notional Values	16,700,000,000	19,100,000,000
Designated as Hedging Instrument [Member] \| Fair Value [Member]
Derivative [Line Items]
Total Derivative Notional Values	11,200,000,000	12,600,000,000
Trading [Member]
Derivative [Line Items]
Total Derivative Notional Values	43,800,000,000	72,700,000,000
Interest Rate Swaps [Member]
Derivative [Line Items]
Total Derivative Notional Values	51,000,000,000.0	79,200,000,000
Interest Rate Swaps [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow [Member]
Derivative [Line Items]
Total Derivative Notional Values	16,700,000,000	19,100,000,000
Interest Rate Swaps [Member] \| Designated as Hedging Instrument [Member] \| Fair Value [Member]
Derivative [Line Items]
Total Derivative Notional Values	7,500,000,000	8,600,000,000
Interest Rate Swaps [Member] \| Trading [Member]
Derivative [Line Items]
Total Derivative Notional Values	26,800,000,000	51,500,000,000
Floor Income Contracts [Member]
Derivative [Line Items]
Total Derivative Notional Values	17,000,000,000.0	21,200,000,000
Floor Income Contracts [Member] \| Trading [Member]
Derivative [Line Items]
Total Derivative Notional Values	17,000,000,000.0	21,200,000,000
Cross-Currency Interest Rate Swaps [Member]
Derivative [Line Items]
Total Derivative Notional Values	3,700,000,000	4,000,000,000.0
Cross-Currency Interest Rate Swaps [Member] \| Designated as Hedging Instrument [Member] \| Fair Value [Member]
Derivative [Line Items]
Total Derivative Notional Values	$ 3,700,000,000	$ 4,000,000,000.0

Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Use of Estimates

Our financial reporting and accounting policies conform to generally accepted accounting principles in the United States of America (GAAP). The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Uncertain and volatile market and economic conditions increase the risk and complexity of the judgments in these estimates and actual results could differ from estimates. Accounting policies that include the most significant judgments, estimates and assumptions include the allowance for loan losses, goodwill and intangible asset impairment assessment and the amortization of loan premiums and discounts using the effective interest rate method.

Consolidation

The consolidated financial statements include the accounts of Navient Corporation and its majority-owned and controlled subsidiaries and those Variable Interest Entities (VIEs) for which we are the primary beneficiary, after eliminating the effects of intercompany accounts and transactions.

2. Significant Accounting Policies (Continued)

We consolidate any VIEs where we have determined we are the primary beneficiary. A VIE is a legal entity that does not have sufficient equity at risk to finance its own operations, or whose equity holders do not have the power to direct the activities that most significantly affect the economic performance of the entity, or whose equity holders do not share proportionately in the losses or benefits of the entity. The primary beneficiary of the VIE is the entity which has both: (1) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (2) the obligation to absorb losses or receive benefits of the entity that could potentially be significant to the VIE. As it relates to our securitizations and other secured borrowing facilities that are VIEs as of December 31, 2020 that we consolidate, we are the primary beneficiary as we are the servicer of the related education loan assets and own the Residual Interest of the securitization trusts and secured borrowing facilities.

Fair Value Measurement

We use estimates of fair value in applying various accounting standards for our financial statements. Fair value measurements are used in one of four ways:

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In the balance sheet with changes in fair value recorded in the statement of income;

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In the balance sheet with changes in fair value recorded in the accumulated other comprehensive income section of the statement of changes in stockholders’ equity;

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In the balance sheet for instruments carried at lower of cost or fair value with impairment charges recorded in the statement of income; and

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In the notes to the financial statements.

Fair value is defined as the price to sell an asset or transfer a liability in an orderly transaction between willing and able market participants. In general, our policy in estimating fair value is to first look at observable market prices for identical assets and liabilities in active markets, where available. When these are not available, other inputs are used to model fair value such as prices of similar instruments, yield curves, volatilities, prepayment speeds, default rates and credit spreads, relying first on observable data from active markets. Depending on current market conditions, additional adjustments to fair value may be based on factors such as liquidity and credit spreads. Transaction costs are not included in the determination of fair value. When possible, we seek to validate the model’s output to market transactions. Depending on the availability of observable inputs and prices, different valuation models could produce materially different fair value estimates. The values presented may not represent future fair values and may not be realizable.

We categorize our fair value estimates based on a hierarchical framework associated with three levels of price transparency utilized in measuring financial instruments at fair value. Classification is based on the lowest level of input that is significant to the fair value of the instrument. The three levels are as follows:

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Level 1 — Quoted prices (unadjusted) in active markets for identical assets or liabilities that we have the ability to access at the measurement date. The types of financial instruments included in level 1 are highly liquid instruments with quoted prices.

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Level 2 — Inputs from active markets, other than quoted prices for identical instruments, are used to determine fair value. Significant inputs are directly observable from active markets for substantially the full term of the asset or liability being valued.

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Level 3 — Pricing inputs significant to the valuation are unobservable. Inputs are developed based on the best information available. However, significant judgment is required by us in developing the inputs.

Loans

Loans, consisting of federally insured education loans and Private Education Loans, that we have the ability and intent to hold for the foreseeable future are classified as held-for-investment and are carried at amortized cost. Amortized cost includes the unamortized premiums, discounts, and capitalized origination costs and fees, all of which are amortized to interest income as further discussed below. Loans which are held-for-investment also have an allowance for loan loss. Any loans we have not classified as held-for-investment are classified as held-for-sale and carried at the lower of cost or fair value. Loans are classified as held-for-sale when we have the intent and ability to sell such loans. Loans which are held-for-sale do not have the associated premium, discount, and capitalized origination costs and fees amortized into interest income. In addition, once a loan is classified as held-for-sale, any allowance for loan losses that existed immediately prior to the reclassification to held-for-sale is reversed through provision.

Allowance for Loan Losses

On January 1, 2020, we adopted ASU No. 2016-13, “Financial Instruments — Credit Losses,” which requires measurement and recognition of an allowance for loan loss that estimates the remaining current expected credit losses (CECL) for financial assets measured at amortized cost held at the reporting date. Our prior allowance for loan loss was an incurred loss model. As a result, the new guidance resulted in an increase to our allowance for loan losses. The new standard impacts the allowance for loan losses related to our Private Education Loans and FFELP Loans.

The standard was applied through a cumulative-effect adjustment to retained earnings (net of tax) as of January 1, 2020, the effective date, for the education loans on our balance sheet as of that date (except for the $70 million Purchased Credit Deteriorated (PCD) portfolio where the related $43 million allowance is recorded as an increase to the basis of the loans). Subsequently, changes in the estimated remaining current expected credit losses, including estimated losses on newly originated education loans, are recorded through provision (net income). This standard represents a significant change from prior GAAP and has resulted in material changes to the Company’s accounting for the allowance for loan losses.

Related to this new standard:

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We have determined that, for modeling current expected credit losses, we can reasonably estimate expected losses that incorporate current and forecasted economic conditions over a “reasonable and supportable” period. For Private Education Loans, we incorporate a reasonable and supportable forecast of various macro-economic variables over the remaining life of the loans. The development of the reasonable and supportable forecast incorporates an assumption that each macro-economic variable will revert to a long-term expectation starting in years 2-4 of the forecast and largely completing within the first five years of the forecast. For FFELP Loans, after a three-year reasonable and supportable period, there is an immediate reversion to a long-term expectation. The models used to project losses utilize key credit quality indicators of the loan portfolio and predict how those attributes are expected to perform in connection with the forecasted economic conditions. These losses are calculated on an undiscounted basis. For Private Education Loans, we utilize a transition rate model that estimates the probability of prepayment and default and apply the loss given default. For FFELP Loans, we use historical transition rates to determine prepayments and defaults. The forecasted economic conditions used in our modeling of expected losses are provided by a third party. The primary economic metrics we use in the economic forecast are unemployment, GDP, interest rates, consumer loan delinquency rates and consumer income. Several forecast scenarios are provided which represent the baseline economic expectations as well as favorable and adverse scenarios. We analyze and evaluate the alternative scenarios for reasonableness and determine the appropriate weighting of these alternative scenarios based upon the current economic conditions and our view of the likelihood and risks of the alternative scenarios. We project losses at the loan level and make estimates regarding prepayments, recoveries on defaults and reasonably expected new Troubled Debt Restructurings (TDRs).

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Separately, as it relates to interest rate concessions granted as part of our private education loan modification program, a discounted cash flow model is used to calculate the amount of interest forgiven for loans currently in the program. The present value of this interest rate concession is included in our allowance for loan loss.

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Charge-offs include the discount or premium related to such defaulted loan.

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CECL requires our expected future recoveries on charged-off loans to be presented within the allowance for loan loss whereas previously, we accounted for our receivable for partially charged-off loans ($588 million as of December 31, 2019) as part of our Private Education Loan portfolio. This change is only a change in classification on the balance sheet and did not impact retained earnings at adoption of CECL or provision and net income post-adoption.

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Once our loss model calculations are performed, we review the adequacy of the allowance for loan losses and determine if qualitative adjustments need to be made. These adjustments may include, but are not limited to, changes in lending and servicing and collection policies and practices, as well as the effect of other external factors such as the economy and changes in legal or regulatory requirements that impact the amount of future credit losses.

2. Significant Accounting Policies (Continued)

The total allowance for loan losses increased by $802 million upon adoption on January 1, 2020 (excluding the impact of the balance sheet reclassifications related to the expected future recoveries and PCD portfolio discussed above). This had a corresponding reduction to equity of $620 million.

(Dollars in millions)	FFELP Loans		Private Education Loans			Total
Allowance as of December 31, 2019 (prior to CECL)	$	64	$	1,048		$	1,112
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses on non-PCD portfolio⁽¹⁾		260		542			802
Current expected credit losses on PCD portfolio⁽²⁾		—		43			43
Reclassification of the expected future recoveries on charged-off loans⁽³⁾		—		(588	)		(588	)
Net increase to allowance for loan losses under CECL		260		(3	)		257
Allowance as of January 1, 2020 after CECL	$	324	$	1,045		$	1,369

⁽¹⁾	Recorded net of tax through retained earnings. Resulted in a $620 million reduction to equity.

⁽²⁾	Recorded as an increase in basis of the loans. No impact to equity.

⁽³⁾	Reclassification of the expected future recoveries on charged-off loans (previously referred to as the receivable for partially charged-off loans) from the Private Education Loan balance to the allowance for loan losses. No impact to equity.

The $155 million provision for loan losses in 2020 primarily related to an increase in expected losses due to COVID-19’s negative impact on the current and forecasted economic conditions. This increase in expected losses was largely reflected in the allowance for loan losses as of June 30, 2020 as we believe there was not a significant change in the credit quality of the portfolio or in the current and forecasted economic conditions between June 30, 2020 and December 31, 2020. These conclusions and adjustments were based on an evaluation of current and forecasted economic conditions directly taking into consideration the negative impact of COVID-19 on the U.S. economy. We evaluated and considered several forecasted economic scenarios when making these conclusions and adjustments. We also considered the characteristics of our loan portfolio and its expected behavior in the forecasted economic scenarios. The provision for loan losses in 2020 related to COVID-19 is directly related to changes in the following assumptions regarding the current and forecasted economic conditions since January 1, 2020 (when CECL was implemented): an increase in unemployment, a decrease in GDP, a decrease in interest rates, an increase in consumer loan delinquency rates and a decrease in consumer income. If future economic conditions as a result of COVID-19 are significantly worse than what was assumed as a part of this assessment, specifically related to the severity and length of the downturn and subsequent recovery, it could result in additional provision for loan loss being recorded in future periods.

At the end of each month, for Private Education loans that are 212 days past due, we charge off the estimated loss of a defaulted loan balance. Actual recoveries are applied against the remaining loan balance that was not charged off. We refer to this remaining loan balance as the “expected future recoveries on charged-off loans.” If actual periodic recoveries are less than expected, the difference is immediately charged off through the allowance for Private Education Loan losses with an offsetting reduction in the expected future recoveries on charged-off loans. If actual periodic recoveries are greater than expected, they will be reflected as a recovery through the allowance for Private Education Loan losses once the cumulative recovery amount exceeds the cumulative amount originally expected to be recovered.

FFELP Loans are insured as to their principal and accrued interest in the event of default subject to a Risk Sharing level based on the date of loan disbursement. These insurance obligations are supported by contractual rights against the United States. For loans disbursed after October 1, 1993, and before July 1, 2006, we receive 98% reimbursement on all qualifying default claims. For loans disbursed on or after July 1, 2006, we receive 97% reimbursement. For loans disbursed prior to October 1, 1993, we receive 100% reimbursement.

2. Significant Accounting Policies (Continued)

Allowance for Loan Losses Prior to the Adoption of CECL

Private Education Loans

We consider a loan to be impaired when, based on current information, a loss has been incurred and it is probable that we will not receive all contractual amounts due. When making our assessment as to whether a loan is impaired, we also take into account more than insignificant delays in payment. We generally evaluate impaired loans on an aggregate basis by grouping similar loans. Impaired loans also include those loans which are individually assessed for impairment at a loan level, such as in a troubled debt restructuring (TDR). We maintain an allowance for loan losses at an amount sufficient to absorb losses incurred in our portfolios at the reporting date based on a projection of estimated probable credit losses incurred in the portfolio.

Our Private Education Loan portfolio contains TDR and non-TDR loans. For customers experiencing financial difficulty, certain Private Education Loans for which we have granted a forbearance of greater than three months, an interest rate reduction or an extended repayment plan are classified as TDRs. The allowance requirements are different based on these designations. In determining the allowance for loan losses on our non-TDR portfolio, we estimate the principal amount of loans that will default over the next two years (two years being the expected period between a loss event and default) and how much we expect to recover over time related to the defaulted amount. Expected defaults less our expected recoveries equal the allowance related to this portfolio. Our historical experience indicates that, on average, the time between the date that a customer experiences a default causing event (i.e., the loss trigger event) and the date that we charge off the unrecoverable portion of that loan is two years. Separately, for our TDR portfolio, we estimate an allowance amount sufficient to cover life-of-loan expected losses through an impairment calculation based on the difference between the loan’s basis and the present value of expected future cash flows (which would include life-of-loan default and recovery assumptions) discounted at the loan’s original effective interest rate. Our TDR portfolio is comprised mostly of loans with forbearance usage greater than three months and interest rate reductions. The separate allowance estimates for our TDR and non-TDR portfolios are combined into our total allowance for Private Education Loan losses.

In estimating both the non-TDR and TDR allowance amounts, we start with historical experience of customer default behavior. We make judgments about which historical period to start with and then make further judgments about whether that historical experience is representative of future expectations and whether additional adjustments may be needed to those historical default rates. We also take the economic environment into consideration when calculating the allowance for loan losses. We analyze key economic statistics and the effect we expect them to have on future defaults. Key economic statistics analyzed as part of the allowance for loan losses are primarily unemployment rates. Our allowance for loan losses is estimated using an analysis of delinquent and current accounts. Our model is used to estimate the likelihood that a loan may progress through the various delinquency stages and ultimately charge off. The evaluation of the allowance for loan losses is inherently subjective, as it requires material estimates that may be susceptible to significant changes. The estimate for the allowance for loan losses is subject to a number of assumptions. If actual future performance in delinquency, charge-offs and recoveries are significantly different than estimated, this could materially affect our estimate of the allowance for loan losses and the related provision for loan losses on our income statement.

We determine the collectability of our Private Education Loan portfolio by evaluating certain risk characteristics. We consider credit score (FICO), loan status, loan seasoning, existence of a cosigner and school type as the key credit quality indicators because they have the most significant effect on our determination of the adequacy of our allowance for loan losses.

2. Significant Accounting Policies (Continued)

To estimate the probable credit losses incurred in the loan portfolio at the reporting date, we use historical experience of customer payment behavior in connection with the key credit quality indicators and incorporate management expectations regarding macroeconomic and collection performance factors. Our model is based upon the most recent twelve months of actual collection experience as the starting point for the non-TDR portfolio and the most recent approximate 15 years for the TDR portfolio and applies expected macroeconomic changes and collection procedure changes to estimate expected losses caused by loss events incurred as of the balance sheet date. Our model for the non-TDR portfolio places a greater emphasis on the more recent default experience rather than the default experience for older historical periods, as we believe the more recent default experience is more indicative of the probable losses incurred in the loan portfolio today that will default over the next two years. The TDR portfolio uses a longer historical default experience since we are projecting life of loan remaining losses. Similar to estimating defaults, we use historical customer payment behavior to estimate the timing and amount of future recoveries on charged-off loans. We use judgment in determining whether historical performance is representative of what we expect to collect in the future. We then apply the default and collection rate projections to each category of loans. Once the quantitative calculation is performed, we review the adequacy of the allowance for loan losses and determine if qualitative adjustments need to be considered. Additionally, we consider changes in laws and regulations that could potentially impact the allowance for loan losses.

FFELP Loans

Similar to the allowance for Private Education Loan losses, the allowance for FFELP Loan losses uses historical experience of customer default behavior and a two-year loss confirmation period to estimate the credit losses incurred in the loan portfolio at the reporting date. We apply the default rate projections, net of applicable Risk Sharing, to each category for the current period to perform our quantitative calculation. Once the quantitative calculation is performed, we review the adequacy of the allowance for loan losses and determine if qualitative adjustments need to be considered. For FFELP Loans that have lost their government insurance and have been charged off, any subsequent cash recoveries benefit the allowance for loan losses when received.

Investments

Other investments are primarily receivables for cash collateral posted to derivative counterparties.

Cash and Cash Equivalents

Cash and cash equivalents can include term federal funds, Eurodollar deposits, commercial paper, asset-backed commercial paper (ABCP), CDs, treasuries and money market funds with original terms to maturity of less than three months.

Restricted Cash and Investments

Restricted cash primarily includes amounts held in education loan securitization trusts and other secured borrowings. This cash must be used to make payments related to trust obligations. Amounts on deposit in these accounts are primarily the result of timing differences between when principal and interest is collected on the trust assets and when principal and interest is paid on trust liabilities.

Securities pledged as collateral related to our derivative portfolio, where the counterparty has rights to replace the securities, are classified as restricted. When the counterparty does not have these rights, the security is recorded in investments and disclosed as pledged collateral in the notes. Additionally, certain counterparties require cash collateral pledged to us to be segregated and held in restricted cash accounts.

Goodwill and Acquired Intangible Assets

Acquisitions are accounted for under the acquisition method of accounting which results in the Company allocating the purchase price to the fair value of the acquired assets, liabilities and non-controlling interests, if any, with the remaining purchase price allocated to goodwill.

Goodwill is not amortized but is tested periodically for impairment. We test goodwill for impairment annually as of October 1 at the reporting unit level, which is the same as or one level below a business segment. Goodwill is also tested at interim periods if an event occurs or circumstances change that would indicate the carrying amount may be impaired.

2. Significant Accounting Policies (Continued)

We complete a goodwill impairment analysis which may be a qualitative or a quantitative analysis depending on the facts and circumstances associated with the reporting unit. In conjunction with a qualitative impairment analysis, we assess relevant qualitative factors to determine whether it is “more-likely-than-not” that the fair value of a reporting unit is less than its carrying amount. The “more-likely-than-not” threshold is defined as having a likelihood of more than 50%. If, based on first assessing impairment utilizing a qualitative approach, we determine it is “more-likely-than-not” that the fair value of the reporting unit is less than its carrying amount, we will also complete a quantitative impairment analysis. In conjunction with a quantitative impairment analysis, we compare the fair value of the reporting unit to the reporting unit’s carrying value, including goodwill. If the carrying value of the reporting unit exceeds the fair value, goodwill is impaired in an amount equal to the amount by which the carrying value exceeds the fair value of the reporting unit not to exceed the goodwill amount attributed to the reporting unit.

Acquired intangible assets include, but are not limited to, trade names, customer and other relationships, and non-compete agreements. Acquired intangible assets with finite lives are amortized over their estimated useful lives in proportion to their estimated economic benefit. Finite-lived acquired intangible assets are reviewed for impairment using an undiscounted cash flow analysis when an event occurs or circumstances change indicating the carrying amount of a finite-lived asset or asset group may not be recoverable. If the carrying amount of the asset or asset group exceeds the undiscounted cash flows, the fair value of the asset or asset group is determined using an acceptable valuation technique. An impairment loss would be recognized if the carrying amount of the asset
or asset group exceeds the fair value of the asset or asset group. The impairment loss recognized would be the difference between the carrying amount and fair value.

Securitization Accounting

Securitization Accounting Our securitizations use a two-step structure with a special purpose entity that legally isolates the transferred assets from us, even in the event of bankruptcy. Transactions receiving sale treatment are also structured to ensure that the holders of the beneficial interests issued are not constrained from pledging or exchanging their interests, and that we do not maintain effective control over the transferred assets. If these criteria are not met, then the transaction is accounted for as an on-balance sheet secured borrowing. In all cases, irrespective of whether they qualify as accounting sales our securitizations are legally structured to be sales of assets that isolate the transferred assets from us. If a securitization qualifies as a sale, we then assess whether we are the primary beneficiary of the securitization trust (VIE) and are required to consolidate such trust. If we are the primary beneficiary, then no gain or loss is recognized. See “Consolidation” of this Note 2 for additional information regarding the accounting rules for consolidation when we are the primary beneficiary of these trusts.

Irrespective of whether a securitization receives sale or on-balance sheet treatment, our continuing involvement with our securitization trusts is generally limited to:

•	Owning equity certificates or other certificates of certain trusts and, in certain cases, securities retained for the purpose of complying with risk retention requirements under securities laws.

•	Lending to certain trusts, under a revolving credit, amounts necessary to cover temporary cash flow needs of the trust. These amounts are repaid to us on subordinated basis with interest at a market rate.

•	The servicing of the education loan assets within the securitization trusts, on both a pre- and post-default basis.

•	Our acting as administrator for the securitization transactions we sponsored, which includes remarketing certain bonds at future dates.

•	Our responsibilities relative to representation and warranty violations.

•	Temporarily advancing to the trust certain borrower benefits afforded the borrowers of education loans that have been securitized. These advances subsequently are returned to us in the next quarter.

•	Certain back-to-back derivatives entered into by us contemporaneously with the execution of derivatives by certain Private Education Loan securitization trusts.

•	The option held by us to buy certain delinquent loans from certain Private Education Loan securitization trusts.

•	The option to exercise the clean-up call and purchase the education loans from the trust when the asset balance is 10% or less of the original loan balance.

•	The option, on some trusts, to purchase education loans aggregating up to 10% of the trust’s initial pool balance.

•	The option (in certain trusts) to call rate reset notes in instances where the remarketing process has failed.

2. Significant Accounting Policies (Continued)

The investors of the securitization trusts have no recourse to our other assets should there be a failure of the trusts to pay when due. Generally, the only arrangements under which we have to provide financial support to the trusts are representation and warranty violations requiring the buyback of loans.

Under the terms of the transaction documents of certain trusts, we have, from time to time, exercised our options to purchase delinquent loans from Private Education Loan trusts, to purchase the remaining loans from trusts once the loan balance falls below 10% of the original amount, to purchase education loans up to 10% of the trust’s initial balance, or to call rate reset notes. Certain trusts maintain financial arrangements with third parties also typical of securitization transactions, such as derivative contracts (swaps).

We do not record servicing assets or servicing liabilities when our securitization trusts are consolidated. As of December 31, 2020, we had $13 million of servicing assets on our balance sheet, recorded in connection with asset sales where we retained the servicing.

Education Loan Interest Income

For loans classified as held-for-investment, we recognize education loan interest income as earned, adjusted for the amortization of premiums (which includes premiums from loan purchases and capitalized direct origination costs), discounts and Repayment Borrower Benefits. These adjustments result in income being recognized based upon the expected yield of the loan over its life after giving effect to expected prepayments. We amortize premium and discount on education loans using a Constant Prepayment Rate (CPR) which measures the rate at which loans in the portfolio pay down principal compared to their stated terms. In determining the CPR, we only consider payments made in excess of contractually required payments. This would include loan refinancing and consolidations and other early payoff activity. For Repayment Borrower Benefits, the estimates of their effect on education loan yield are based on analyses of historical payment behavior of customers who are eligible for the incentives and its effect on the ultimate qualification rate for these incentives. We regularly evaluate the assumptions used to estimate the prepayment speeds and the qualification rates used for Repayment Borrower Benefits. In instances where there are changes to the assumptions, amortization is adjusted on a cumulative basis to reflect the change since the acquisition of the loan. We do not amortize any premiums, discounts or other adjustments to the basis of education loans when they are classified as held-for-sale.

Interest Expense

Interest expense is based upon contractual interest rates adjusted for the amortization of debt issuance costs, premiums and discounts. Our interest expense is also adjusted for net payments/receipts related to interest rate and foreign currency swap agreements that qualify and are designated as hedges, as well as the mark-to-market impact of derivatives and debt in fair value hedge relationships. Interest expense also includes the amortization of deferred gains and losses on closed hedge transactions that qualified as hedges. Amortization of debt issuance costs, premiums, discounts and terminated hedge-basis adjustments are recognized using the effective interest rate method.

Servicing Revenue

We perform loan servicing functions for third parties in return for a servicing fee. Our compensation is typically based on a per-unit fee arrangement or a percentage of the loans outstanding. We recognize servicing revenues associated with these activities based upon the contractual arrangements as the services are rendered. We recognize late fees on third-party serviced loans as well as on loans in our portfolio according to the contractual provisions of the promissory notes, as well as our expectation of collectability.

Asset Recovery And Business Processing Revenue

Asset Recovery and Business Processing Revenue

We account for certain asset recovery and business processing contract revenue (herein referred to as revenue from contracts with customers) in accordance with ASC 606, “Revenue from Contracts with Customers.” (All Business Processing segment and the majority of the Federal Education Loan segment asset recovery and business processing revenue is accounted for under ASC 606.) Revenue earned by our Federal Education Loans segment is derived from asset recovery activities related to the collection of delinquent education loans on behalf of ED, Guarantor agencies and other institutions, as well as certain other guarantor activities. Revenue earned by our Business Processing segment is derived from government services, which includes receivables management services and account processing solutions, and healthcare services, which includes revenue cycle management services.

2. Significant Accounting Policies (Continued)

Most of our revenue from contracts with customers is derived from long-term contracts, the duration of which is expected to span more than one year. These contracts are billable monthly, as services are rendered, based on a percentage of the balance collected or the transaction processed, a flat fee per transaction or a stated rate per the service performed. In accordance with ASC 606, the unit of account is a contractual performance obligation, a promise to provide a distinct good or service to a customer. The transaction price is allocated to each distinct performance obligation when or as the good or service is transferred to the customer and the obligation is satisfied.

Distinct performance obligations are identified based on the services specified in the contract that are capable of being distinct such that the customer can benefit from the service on its own or together with other resources that are available from the Company or a third party, and are also distinct in the context of the contract such that the transfer of the services is separately identifiable from other services promised in the contract. Most of our contracts include integrated service offerings that include obligations that are not separately identifiable and distinct in the context of our contracts. Accordingly, our contracts generally have a single performance obligation. A limited number of full-service offerings include multiple performance obligations.

Substantially all our revenue is variable revenue which is recognized over time as our customers receive and consume the benefit of our services in an amount consistent with monthly billings. Accordingly, we do not disclose variable consideration associated with the remaining performance obligation as we have recognized revenue in the amount we have the right to invoice for services performed. Our fees correspond to the value the customer has realized from our performance of each increment of the service (for example, an individual transaction processed or collection of a past due balance).

Transfer of Financial Assets and Extinguishments of Liabilities

Our securitizations and other secured borrowings are generally accounted for as on-balance sheet secured borrowings. See “Securitization Accounting” of this Note 2 for further discussion on the criteria assessed to determine whether a transfer of financial assets is a sale or a secured borrowing. If a transfer of loans qualifies as a sale, we derecognize the loan and recognize a gain or loss as the difference between the carrying basis of the loan sold and liabilities retained and the compensation received.

We periodically repurchase our outstanding debt in the open market or through public tender offers. We record a gain or loss on the early extinguishment of debt based upon the difference between the carrying cost of the debt and the amount paid to the third party and net of hedging gains and losses when the debt is in a qualifying hedge relationship.

We recognize the results of a transfer of loans and the extinguishment of debt based upon the settlement date of the transaction.

Derivative Accounting

Derivative instruments that are used as part of our interest rate and foreign currency risk management strategy include interest rate swaps, cross-currency interest rate swaps, and interest rate floor contracts. The accounting for derivative instruments requires that every derivative instrument, including certain derivative instruments embedded in other contracts, be recorded on the balance sheet as either an asset or liability measured at its fair value. As more fully described below, if certain criteria are met, derivative instruments are classified and accounted for by us as either fair value or cash flow hedges. If these criteria are not met, the derivative financial instruments are accounted for as trading. Derivative positions are recorded as net positions by counterparty based on master netting arrangements exclusive of accrued interest and cash collateral held or pledged. Many of our derivatives, mainly fixed to variable or variable to fixed interest rate swaps and cross-currency interest rate swaps, qualify as effective hedges. For these derivatives, at the inception of the hedge relationship, the following is documented: the relationship between the hedging instrument and the hedged items (including the hedged risk, the method for assessing effectiveness, and the results of the upfront effectiveness testing), and the risk management objective and strategy for undertaking the hedge transaction. Each derivative is designated to either a specific (or pool of) asset(s) or liability(ies) on the balance sheet or expected future cash flows and designated as either a “fair value” or a “cash flow” hedge. The assessment of the hedge’s effectiveness is performed at inception and on an ongoing basis, generally using regression testing. For hedges of a pool of assets or liabilities, tests are performed to demonstrate the similarity of individual instruments of the pool. When it is determined that a derivative is not currently an effective hedge, ineffectiveness is recognized for the full change in value of the derivative with no offsetting mark-to-market of the hedged item for the current period. If it is also determined the hedge will not be effective in the future, we discontinue the hedge accounting prospectively, cease recording changes in the fair value of the hedged item, and begin amortization of any basis adjustments that exist related to the hedged item.

2. Significant Accounting Policies (Continued)

Fair Value Hedges

Fair value hedges are generally used by us to hedge the exposure to changes in the fair value of a recognized fixed rate asset or liability. We enter into interest rate swaps to economically convert fixed rate assets into variable rate assets and fixed rate debt into variable rate debt. We also enter into cross-currency interest rate swaps to economically convert foreign currency denominated fixed and floating debt to U.S. dollar denominated variable debt. For fair value hedges, we generally consider all components of the derivative’s gain and/or loss when assessing hedge effectiveness and generally hedge changes in fair values due to interest rates or interest rates and foreign currency exchange rates. For fair value hedges, both the derivative and the hedged item (for the risk being hedged) are marked-to-market through net interest income with any difference reflecting ineffectiveness.

Cash Flow Hedges

We use cash flow hedges to hedge the exposure to variability in cash flows for a forecasted debt issuance and for exposure to variability in cash flows of floating rate debt or assets. This strategy is used primarily to minimize the exposure to volatility from future changes in interest rates. For cash flow hedges, the change in the fair value of the derivative is recorded in other comprehensive income, net of tax, and recognized in earnings in the same period as the earnings effects of the hedged item. In the case of a forecasted debt issuance, gains and losses are reclassified to earnings over the period which the stated hedged transaction affects earnings. If we determine it is not probable that the anticipated transaction will occur, gains and losses are reclassified immediately to earnings. In assessing hedge effectiveness, generally all components of each derivative’s gains or losses are included in the assessment. We generally hedge exposure to changes in cash flows due to changes in interest rates or total changes in cash flow.

Trading Activities

When derivative instruments do not qualify as hedges, they are accounted for as trading instruments where all changes in fair value are recorded through earnings with no consideration for the corresponding change in fair value of the economically hedged item. Some of our derivatives, primarily Floor Income Contracts, basis swaps and at times, certain other LIBOR swaps do not qualify for hedge accounting treatment. Regardless of the accounting treatment, we consider these derivatives to be economic hedges for risk management purposes. We use this strategy to minimize our exposure to changes in interest rates.

The “gains (losses) on derivative and hedging activities, net” line item in the consolidated statements of income includes the mark-to-market gains and losses of our derivatives that do not qualify for hedge accounting, as well as the realized changes in fair value related to derivative net settlements and dispositions that do not qualify for hedge accounting.

Accounting for Stock-Based Compensation

We recognize stock-based compensation cost in our statements of income using the fair value-based method. Under this method we determine the fair value of the stock-based compensation at the time of the grant and recognize the resulting compensation expense over the grant’s vesting period. We record stock-based compensation expense net of estimated forfeitures and as such, only those stock-based awards that we expect to vest are recorded. We estimate the forfeiture rate based on historical forfeitures of equity awards and adjust the rate to reflect changes in facts and circumstances, if any. Ultimately, the total expense recognized over the vesting period will equal the fair value of awards that actually vest.

Restructuring and Other Reorganization Expenses

From time to time we implement plans to restructure our business. In conjunction with these restructuring plans, involuntary benefit arrangements, disposal costs (including contract termination costs and other exit costs), as well as certain other costs that are incremental and incurred as a direct result of our restructuring plans, are classified as restructuring expenses in the consolidated statements of income.

The Company administers the Navient Corporation Employee Severance Plan and the Navient Corporation Executive Severance Plan for Senior Officers (collectively, the Severance Plan). The Severance Plan provides severance benefits in the event of termination of the Company’s full-time employees and part-time employees who work at least 24 hours per week. The Severance Plan establishes specified benefits based on base salary, job level immediately preceding termination and years of service upon involuntary termination of employment. The benefits payable under the Severance Plan relate to past service, and they accumulate and vest. Accordingly, we recognize severance expenses to be paid pursuant to the Severance Plan when payment of such benefits is probable and can be reasonably estimated. Such benefits include severance pay calculated based on the Severance Plan, medical and dental benefits, and outplacement services expenses.

Contract termination costs are expensed at the earlier of (1) the contract termination date or (2) the cease use date under the contract. Other exit costs are expensed as incurred and classified as restructuring expenses if (1) the cost is incremental to and incurred as a direct result of planned restructuring activities and (2) the cost is not associated with or incurred to generate revenues subsequent to our consummation of the related restructuring activities.

Other reorganization expenses include certain internal costs and third-party costs incurred in connection with our cost reduction initiatives.

During 2020 and 2019, the Company incurred $9 million and $6 million, respectively, of restructuring/other reorganization expense in connection with an effort that will reduce costs and improve operating efficiency. These charges were primarily related to facility lease terminations and severance-related costs.

Income Taxes

We account for income taxes under the asset and liability approach which requires the recognition of deferred tax liabilities and assets for the expected future tax consequences of temporary differences between the carrying amounts and tax basis of our assets and liabilities. To the extent tax laws change, deferred tax assets and liabilities are adjusted in the period that the tax change is enacted.

“Income tax expense/(benefit)” includes (i) deferred tax expense/(benefit), which represents the net change in the deferred tax asset or liability balance during the year plus any change in a valuation allowance and (ii) current tax expense/(benefit), which represents the amount of tax currently payable to or receivable from a tax authority plus amounts accrued for unrecognized tax benefits. Income tax expense/(benefit) excludes the tax effects related to adjustments recorded in equity.

If we have an uncertain tax position, then that tax position is recognized only if it is more likely than not to be sustained upon examination based on the technical merits of the position. The amount of tax benefit recognized in the financial statements is the largest amount of benefit that is more than 50% likely of being sustained upon ultimate settlement of the uncertain tax position. We recognize interest related to unrecognized tax benefits in income tax expense/(benefit) and penalties, if any, in operating expenses.

Earnings (Loss) per Common Share

We compute earnings (loss) per common share (EPS) by dividing net income allocated to common shareholders by the weighted average common shares outstanding. Diluted earnings per common share is computed by dividing income allocated to common shareholders by the weighted average common shares outstanding plus amounts representing the dilutive effect of stock options outstanding, restricted stock, restricted stock units, and the outstanding commitment to issue shares under the Employee Stock Purchase Plan. See “Note 10 — Earnings (Loss) per Common Share” for further discussion.

Recently Issued Accounting Pronouncements

Effective in 2020

Allowance for Loan Losses

Goodwill

On January 1, 2020, we adopted ASU No. 2017-04, "Intangibles – Goodwill and Other: Simplifying the Test for Goodwill Impairment.” The new standard simplifies the goodwill impairment test by eliminating the requirement to perform step two of the goodwill impairment test when the carrying value of a reporting unit exceeds the reporting unit fair value. Impairment is the amount by which the carrying value exceeds the reporting unit fair value, not to exceed the total allocated reporting unit goodwill. Previously, step two required a hypothetical purchase price allocation when step one indicated potential impairment. This new standard had no impact on 2020 results.

Rate Reform

In March 2020, the FASB issued ASU No. 2020-04, “Reference Rate Reform: Facilitation of the Effects of Reference Rate Reform on Financial Reporting,” which provides relief for companies who are preparing for the discontinuation of interest rates such as the London Interbank Offered Rate (LIBOR). The ASU provides companies with optional guidance in the form of expedients and exceptions related to contract modifications, hedge accounting and held to maturity debt securities to ease the burden of and simplify the accounting associated with transitioning away from LIBOR. This guidance, which will only be available through December 31, 2022, can be applied commencing in March 2020. The Company continues to assess the implications of the discontinuation of LIBOR. Accordingly, the Company has not applied or concluded whether it will apply the expedients and exceptions provided in this new standard.

Allowance for Loan Losses - Allowance for Credit Losses and Recorded Investments in Loans (Detail) - USD ($) $ in Millions		12 Months Ended
	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for Loan Losses
Allowance at beginning of period	$ 1,112.0	$ 1,112.0	$ 1,286.0	$ 1,367.0
Total provision		155.0	258.0	370.0
Charge-offs:
Net adjustment resulting from the change in the charge-off rate		(23.0)	(21.0)	(32.0)
Net charge-offs remaining		(233.0)	(408.0)	(427.0)
Total charge-offs		(256.0)	(429.0)	(459.0)
Decrease in expected future recoveries on charged-off loans		109.0
Reclassification of interest reserve			7.0	8.0
Loan sales and other transactions			(9.0)
Allowance at end of period		1,377.0	1,112.0	1,286.0
Plus: expected future recoveries on charged-off loans		479.0
Allowance at end of period excluding expected future recoveries on charged-off loans		1,856.0
Allowance Ending Balance:
Individually evaluated for impairment - TDR			941.0	1,108.0
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans			171.0	178.0
Loans Ending Balance:
Individually evaluated for impairment - TDR			9,617.0	10,364.0
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans			73,884.0	80,395.0
Purchased Non-Credit Impaired Loans acquired at a discount			4,311.0	5,030.0
Purchased Credit Impaired Loans			201.0	225.0
Ending total loans			88,013.0	96,014.0
FFELP Loans [Member]
Allowance for Loan Losses
Allowance at beginning of period	64.0	64.0	76.0	60.0
Total provision		13.0	30.0	70.0
Charge-offs:
Net charge-offs remaining		(49.0)	(42.0)	(54.0)
Total charge-offs		(49.0)	(42.0)	(54.0)
Allowance at end of period		288.0	64.0	76.0
Allowance at end of period excluding expected future recoveries on charged-off loans		288.0
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans			64.0	76.0
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans			61,589.0	68,880.0
Purchased Non-Credit Impaired Loans acquired at a discount			2,505.0	2,850.0
Ending total loans		$ 58,572.0	$ 64,094.0	$ 71,730.0
Net charge-offs as a percentage of average loans in repayment, excluding the net adjustment resulting from the change in the charge-off rate		0.10%	0.07%	0.09%
Allowance coverage of charge-offs		5.9	1.5	1.4
Allowance as a percentage of the ending total loan balance		0.50%	0.10%	0.11%
Allowance as a percentage of the ending loans in repayment		0.60%	0.12%	0.13%
Average loans in repayment		$ 48,130.0	$ 55,978.0	$ 62,927.0
Ending loans in repayment		48,057.0	53,538.0	59,551.0
ASU 2016-13 [Member]
Allowance for Loan Losses
Allowance at beginning of period	1,369.0	1,369.0
Charge-offs:
Allowance at end of period	1,369.0		1,369.0
ASU 2016-13 [Member] \| FFELP Loans [Member]
Allowance for Loan Losses
Allowance at beginning of period	324.0	324.0
Charge-offs:
Allowance at end of period	324.0		324.0
Private Education Loans [Member]
Allowance for Loan Losses
Allowance at beginning of period	1,048.0	1,048.0	1,201.0	1,297.0
Total provision		142.0	226.0	299.0
Charge-offs:
Net adjustment resulting from the change in the charge-off rate		(23.0)	(21.0)	(32.0)
Net charge-offs remaining		(184.0)	(364.0)	(371.0)
Total charge-offs		(207.0)	(385.0)	(403.0)
Decrease in expected future recoveries on charged-off loans		109.0
Reclassification of interest reserve			7.0	8.0
Loan sales and other transactions			(1.0)
Allowance at end of period		1,089.0	1,048.0	1,201.0
Plus: expected future recoveries on charged-off loans		479.0	588.0
Allowance at end of period excluding expected future recoveries on charged-off loans		1,568.0
Allowance Ending Balance:
Individually evaluated for impairment - TDR			941.0	1,100.0
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans			107.0	101.0
Loans Ending Balance:
Individually evaluated for impairment - TDR			9,617.0	10,336.0
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans			12,286.0	11,464.0
Purchased Non-Credit Impaired Loans acquired at a discount			1,806.0	2,180.0
Purchased Credit Impaired Loans			201.0	225.0
Ending total loans		$ 22,168.0	$ 23,910.0	$ 24,205.0
Net charge-offs as a percentage of average loans in repayment, excluding the net adjustment resulting from the change in the charge-off rate		0.88%	1.67%	1.66%
Net adjustment resulting from the change in charge-off rate as a percentage of average loans in repayment		0.11%	0.10%	0.14%
Allowance coverage of charge-offs		7.6	2.7	3.0
Allowance as a percentage of the ending total loan balance		7.10%	4.38%	4.96%
Allowance as a percentage of the ending loans in repayment		7.50%	4.74%	5.45%
Average loans in repayment		$ 20,790.0	$ 21,859.0	$ 22,312.0
Ending loans in repayment		20,841.0	22,089.0	22,037.0
Private Education Loans [Member] \| ASU 2016-13 [Member]
Allowance for Loan Losses
Allowance at beginning of period	1,045.0	$ 1,045.0
Charge-offs:
Allowance at end of period	$ 1,045.0		1,045.0
Other Loans [Member]
Allowance for Loan Losses
Allowance at beginning of period			9.0	10.0
Total provision			1.0	1.0
Charge-offs:
Net charge-offs remaining			(2.0)	(2.0)
Total charge-offs			(2.0)	(2.0)
Loan sales and other transactions			(8.0)
Allowance at end of period				9.0
Allowance Ending Balance:
Individually evaluated for impairment - TDR				8.0
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans				1.0
Loans Ending Balance:
Individually evaluated for impairment - TDR				28.0
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans			9.0	51.0
Ending total loans			9.0	$ 79.0
Allowance as a percentage of the ending total loan balance				11.52%
Allowance as a percentage of the ending loans in repayment				11.52%
Average loans in repayment			29.0	$ 75.0
Ending loans in repayment			$ 9.0	$ 79.0

Derivative Financial Instruments - Impact of Derivatives on Balance Sheet (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Derivative Assets:
Derivative assets	$ 357	$ 230
Derivative Liabilities:
Derivative liabilities	(533)	(664)
Net total derivatives	(176)	(434)
Designated as Hedging Instrument [Member] \| Fair Value [Member]
Derivative Assets:
Derivative assets	351	226
Derivative Liabilities:
Derivative liabilities	(322)	(575)
Net total derivatives	29	(349)
Trading [Member]
Derivative Assets:
Derivative assets	6	4
Derivative Liabilities:
Derivative liabilities	(211)	(89)
Net total derivatives	(205)	(85)
Interest Rate Swaps [Member]
Derivative Assets:
Derivative assets	329	230
Derivative Liabilities:
Derivative liabilities	(14)	(20)
Interest Rate Swaps [Member] \| Designated as Hedging Instrument [Member] \| Fair Value [Member]
Derivative Assets:
Derivative assets	323	226
Interest Rate Swaps [Member] \| Trading [Member]
Derivative Assets:
Derivative assets	6	4
Derivative Liabilities:
Derivative liabilities	(14)	(20)
Cross-Currency Interest Rate Swaps [Member]
Derivative Assets:
Derivative assets	28
Derivative Liabilities:
Derivative liabilities	(322)	(575)
Cross-Currency Interest Rate Swaps [Member] \| Designated as Hedging Instrument [Member] \| Fair Value [Member]
Derivative Assets:
Derivative assets	28
Derivative Liabilities:
Derivative liabilities	(322)	(575)
Floor Income Contracts [Member]
Derivative Liabilities:
Derivative liabilities	(197)	(68)
Floor Income Contracts [Member] \| Trading [Member]
Derivative Liabilities:
Derivative liabilities	$ (197)	(68)
Other [Member]
Derivative Liabilities:
Derivative liabilities		(1)
Other [Member] \| Trading [Member]
Derivative Liabilities:
Derivative liabilities		$ (1)

Segment Reporting

12 Months Ended

Dec. 31, 2020

Segment Reporting [Abstract]

Segment Reporting

15. Segment Reporting

We monitor and assess our ongoing operations and results based on the following four reportable operating segments: Federal Education Loans, Consumer Lending, Business Processing and Other.

These segments meet the quantitative thresholds for reportable operating segments. Accordingly, the results of operations of these reportable operating segments are presented separately. The underlying operating segments are used by the Company’s chief operating decision maker to manage the business, review operating performance and allocate resources, and qualify to be aggregated as part of the primary reportable operating segments. As discussed further below, we measure the profitability of our operating segments based on Core Earnings net income. Accordingly, information regarding our reportable operating segments net income is provided on a Core Earnings basis.

Federal Education Loans Segment

In this segment, Navient owns FFELP Loans and performs servicing and asset recovery services on our FFELP Loan portfolio. We also service and perform asset recovery services on federal education loans owned by ED and other institutions. Our servicing quality, data-driven strategies, and multichannel education about federal repayment options translates into positive results for the millions of borrowers we serve.

We generate revenue primarily through net interest income on the FFELP Loan portfolio as well as servicing and asset recovery services revenue. This segment is expected to generate significant earnings and cash flow over the remaining life of the portfolio.

The following table includes asset information for our Federal Education Loans segment.

	December 31,
(Dollars in millions)	2020		2019
FFELP Loans, net	$	58,284	$	64,575
Cash and investments⁽¹⁾		1,685		2,043
Other		2,241		2,202
Total assets	$	62,210	$	68,820

⁽¹⁾

Includes restricted cash and investments.

Consumer Lending Segment

In this segment, Navient owns, originates, acquires and services high-quality private education loans. We believe our more than 45 years of experience, product design, digital marketing strategies, and origination and servicing platform provide a unique competitive advantage. We see meaningful opportunities in originating Private Education Loans to financially responsible consumers, generating attractive long-term risk adjusted returns. We generate revenue primarily through net interest income on our Private Education Loan portfolio.

The following table includes asset information for our Consumer Lending segment.

	December 31,
(Dollars in millions)	2020		2019
Private Education Loans, net	$	21,079	$	22,245
Cash and investments⁽¹⁾		828		927
Other		964		931
Total assets	$	22,871	$	24,103

⁽¹⁾

Includes restricted cash and investments.

15. Segment Reporting (Continued)

Business Processing Segment

In this segment, Navient performs business processing services for over 500 government and healthcare clients.

•

Government services: We provide state governments, agencies, court systems, municipalities, and parking and tolling authorities with expert service, leveraging our scale, integrated technology solutions and data-driven approach. Our support enables our clients to better serve their constituents, meet rapidly changing needs, reduce their operating expenses, manage risk and maximize revenue opportunities.

•

Healthcare services: We perform revenue cycle outsourcing, accounts receivable management, extended business office support, consulting engagements and public health programs. We offer customizable solutions for our clients that include hospitals, hospital systems, medical centers, large physician groups, other healthcare providers and departments of public health.

At December 31, 2020 and 2019, the Business Processing segment had total assets of $425 million and $423 million, respectively.

Other Segment

This segment primarily consists of our corporate liquidity portfolio, gains and losses incurred on the repurchase of debt, unallocated expenses of shared services and restructuring/other reorganization expenses.

Unallocated shared services expenses are comprised of costs primarily related to information technology costs related to infrastructure and operations, stock-based compensation expense, accounting, finance, legal, compliance and risk management, regulatory-related expenses, human resources, certain executive management and the board of directors. Regulatory-related expenses include actual settlement amounts as well as third-party professional fees we incur in connection with such regulatory matters and are presented net of any insurance reimbursements for covered costs related to such matters.

At December 31, 2020 and 2019, the Other segment had total assets of $1.9 billion and $1.6 billion, respectively.

15. Segment Reporting (Continued)

Measure of Profitability

We prepare financial statements and present financial results in accordance with GAAP. However, we also evaluate our business segments and present financial results on a basis that differs from GAAP. We refer to this different basis of presentation as Core Earnings. We provide this Core Earnings basis of presentation on a consolidated basis and for each business segment because this is what we review internally when making management decisions regarding our performance and how we allocate resources. We also refer to this information in our presentations with credit rating agencies, lenders and investors. Because our Core Earnings basis of presentation corresponds to our segment financial presentations, we are required by GAAP to provide Core Earnings disclosure in the notes to our consolidated financial statements for our business segments.

Core Earnings are not a substitute for reported results under GAAP. We use Core Earnings to manage our business segments because Core Earnings reflect adjustments to GAAP financial results for two items, discussed below, that can create significant volatility mostly due to timing factors generally beyond the control of management. Accordingly, we believe that Core Earnings provide management with a useful basis from which to better evaluate results from ongoing operations against the business plan or against results from prior periods. Consequently, we disclose this information because we believe it provides investors with additional information regarding the operational and performance indicators that are most closely assessed by management. When compared to GAAP results, the two items we remove to result in our Core Earnings presentations are:

Mark-to-market gains/losses resulting from our use of derivative instruments to hedge our economic risks that do not qualify for hedge accounting treatment or do qualify for hedge accounting treatment but result in ineffectiveness; and

The accounting for goodwill and acquired intangible assets.

While GAAP provides a uniform, comprehensive basis of accounting, for the reasons described above, our Core Earnings basis of presentation does not. Core Earnings are subject to certain general and specific limitations that investors should carefully consider. For example, there is no comprehensive, authoritative guidance for management reporting. Our Core Earnings are not defined terms within GAAP and may not be comparable to similarly titled measures reported by other companies. Accordingly, our Core Earnings presentation does not represent a comprehensive basis of accounting. Investors, therefore, may not be able to compare our performance with that of other financial services companies based upon Core Earnings. Core Earnings results are only meant to supplement GAAP results by providing additional information regarding the operational and performance indicators that are most closely used by management, our board of directors, credit rating agencies, lenders and investors to assess performance.

15. Segment Reporting (Continued)

Segment Results and Reconciliations to GAAP

	Year Ended December 31, 2020
													Adjustments
(Dollars in millions)	Federal Education Loans		Consumer Lending		Business Processing		Other			Total Core Earnings			Reclassi- fications			Additions/ (Subtractions)			Total Adjustments⁽¹⁾			Total GAAP
Interest income:
Education loans	$	1,813	$	1,445	$	—	$	—		$	3,258		$	79		$	(55	)	$	24		$	3,282
Other loans		—		—		—		—			—			—			—			—			—
Cash and investments		7		3		—		6			16			—			—			—			16
Total interest income		1,820		1,448		—		6			3,274			79			(55	)		24			3,298
Total interest expense		1,194		699		—		120			2,013			39			(6	)		33			2,046
Net interest income (loss)		626		749		—		(114	)		1,261			40			(49	)		(9	)		1,252
Less: provisions for loan losses		13		142		—		—			155			—			—			—			155
Net interest income (loss) after provisions for loan losses		613		607		—		(114	)		1,106			40			(49	)		(9	)		1,097
Other income (loss):
Servicing revenue		208		6		—		—			214			—			—			—			214
Asset recovery and business processing revenue		154		—		304		—			458			—			—			—			458
Other income (loss)		9		—		—		11			20			(40	)		(216	)		(256	)		(236	)
Losses on debt repurchases		—		—		—		(6	)		(6	)		—			—			—			(6	)
Total other income (loss)		371		6		304		5			686			(40	)		(216	)		(256	)		430
Expenses:
Direct operating expenses		287		146		254		—			687			—			—			—			687
Unallocated shared services expenses		—		—		—		277			277			—			—			—			277
Operating expenses		287		146		254		277			964			—			—			—			964
Goodwill and acquired intangible asset impairment and amortization		—		—		—		—			—			—			22			22			22
Restructuring/other reorganization expenses		—		—		—		9			9			—			—			—			9
Total expenses		287		146		254		286			973			—			22			22			995
Income (loss) before income tax expense (benefit)		697		467		50		(395	)		819			—			(287	)		(287	)		532
Income tax expense (benefit)⁽²⁾		160		107		11		(90	)		188			—			(68	)		(68	)		120
Net income (loss)	$	537	$	360	$	39	$	(305	)	$	631		$	—		$	(219	)	$	(219	)	$	412

⁽¹⁾	Core Earnings adjustments to GAAP:

	Year Ended December 31, 2020
(Dollars in millions)	Net Impact of Derivative Accounting			Net Impact of Acquired Intangibles			Total
Net interest income (loss) after provisions for loan losses	$	(9	)	$	—		$	(9	)
Total other income (loss)		(256	)		—			(256	)
Goodwill and acquired intangible asset impairment and amortization		—			22			22
Total Core Earnings adjustments to GAAP	$	(265	)	$	(22	)		(287	)
Income tax expense (benefit)								(68	)
Net income (loss)							$	(219	)

⁽²⁾	Income taxes are based on a percentage of net income before tax for the individual reportable segment.

15. Segment Reporting (Continued)

	Year Ended December 31, 2019
												Adjustments
(Dollars in millions)	Federal Education Loans		Consumer Lending		Business Processing		Other			Total Core Earnings		Reclassi- fications			Additions/ (Subtractions)			Total Adjustments⁽¹⁾			Total GAAP
Interest income:
Education loans	$	2,907	$	1,731	$	—	$	—		$	4,638	$	8		$	(68	)	$	(60	)	$	4,578
Other loans		1		1		—		—			2		—			—			—			2
Cash and investments		50		16		—		27			93		—			—			—			93
Total interest income		2,958		1,748		—		27			4,733		8			(68	)		(60	)		4,673
Total interest expense		2,376		980		—		161			3,517		6			(35	)		(29	)		3,488
Net interest income (loss)		582		768		—		(134	)		1,216		2			(33	)		(31	)		1,185
Less: provisions for loan losses		30		228		—		—			258		—			—			—			258
Net interest income (loss) after provisions for loan losses		552		540		—		(134	)		958		2			(33	)		(31	)		927
Other income (loss):
Servicing revenue		229		11		—		—			240		—			—			—			240
Asset recovery and business processing revenue		230		—		258		—			488		—			—			—			488
Other income (loss)		28		1		—		14			43		(41	)		65			24			67
Gains on sales of loans		—		16		—		—			16		—			—			—			16
Gains on debt repurchases		—		—		—		33			33		39			(27	)		12			45
Total other income (loss)		487		28		258		47			820		(2	)		38			36			856
Expenses:
Direct operating expenses		359		156		215		—			730		—			—			—			730
Unallocated shared services expenses		—		—		—		254			254		—			—			—			254
Operating expenses		359		156		215		254			984		—			—			—			984
Goodwill and acquired intangible asset impairment and amortization		—		—		—		—			—		—			30			30			30
Restructuring/other reorganization expenses		—		—		—		6			6		—			—			—			6
Total expenses		359		156		215		260			990		—			30			30			1,020
Income (loss) before income tax expense (benefit)		680		412		43		(347	)		788		—			(25	)		(25	)		763
Income tax expense (benefit)⁽²⁾		155		96		10		(80	)		181		—			(15	)		(15	)		166
Net income (loss)	$	525	$	316	$	33	$	(267	)	$	607	$	—		$	(10	)	$	(10	)	$	597

⁽¹⁾	Core Earnings adjustments to GAAP:

	Year Ended December 31, 2019
(Dollars in millions)	Net Impact of Derivative Accounting			Net Impact of Acquired Intangibles			Total
Net interest income after provisions for loan losses	$	(31	)	$	—		$	(31	)
Total other income (loss)		36			—			36
Goodwill and acquired intangible asset impairment and amortization		—			30			30
Total Core Earnings adjustments to GAAP	$	5		$	(30	)		(25	)
Income tax expense (benefit)								(15	)
Net income (loss)							$	(10	)

⁽²⁾	Income taxes are based on a percentage of net income before tax for the individual reportable segment.

15. Segment Reporting (Continued)

	Year Ended December 31, 2018
												Adjustments
(Dollars in millions)	Federal Education Loans		Consumer Lending		Business Processing		Other			Total Core Earnings		Reclassi- fications			Additions/ (Subtractions)			Total Adjustments⁽¹⁾			Total GAAP
Interest income:
Education loans	$	3,080	$	1,778	$	—	$	—		$	4,858	$	17		$	(70	)	$	(53	)	$	4,805
Other loans		4		2		—		—			6		—			—			—			6
Cash and investments		46		13		—		38			97		—			—			—			97
Total interest income		3,130		1,793		—		38			4,961		17			(70	)		(53	)		4,908
Total interest expense		2,467		1,013		—		192			3,672		8			(12	)		(4	)		3,668
Net interest income (loss)		663		780		—		(154	)		1,289		9			(58	)		(49	)		1,240
Less: provisions for loan losses		70		300		—		—			370		—			—			—			370
Net interest income (loss) after provisions for loan losses		593		480		—		(154	)		919		9			(58	)		(49	)		870
Other income (loss):
Servicing revenue		262		12		—		—			274		—			—			—			274
Asset recovery and business processing revenue		163		—		267		—			430		—			—			—			430
Other income (loss)		24		—		—		6			30		(22	)		(29	)		(51	)		(21	)
Gains on debt repurchases		—		—		—		9			9		13			(3	)		10			19
Total other income (loss)		449		12		267		15			743		(9	)		(32	)		(41	)		702
Expenses:
Direct operating expenses		298		169		229		—			696		—			—			—			696
Unallocated shared services expenses		—		—		—		288			288		—			—			—			288
Operating expenses		298		169		229		288			984		—			—			—			984
Goodwill and acquired intangible asset impairment and amortization		—		—		—		—			—		—			47			47			47
Restructuring/other reorganization expenses		—		—		—		13			13		—			—			—			13
Total expenses		298		169		229		301			997		—			47			47			1,044
Income (loss) before income tax expense (benefit)		744		323		38		(440	)		665		—			(137	)		(137	)		528
Income tax expense (benefit)⁽²⁾		164		71		8		(97	)		146		—			(13	)		(13	)		133
Net income (loss)	$	580	$	252	$	30	$	(343	)	$	519	$	—		$	(124	)	$	(124	)	$	395

⁽¹⁾	Core Earnings adjustments to GAAP:

	Year Ended December 31, 2018
(Dollars in millions)	Net Impact of Derivative Accounting			Net Impact of Acquired Intangibles			Total
Net interest income after provisions for loan losses	$	(49	)	$	—		$	(49	)
Total other income (loss)		(41	)		—			(41	)
Goodwill and acquired intangible asset impairment and amortization		—			47			47
Total Core Earnings adjustments to GAAP	$	(90	)	$	(47	)		(137	)
Income tax expense (benefit)								(13	)
Net income (loss)							$	(124	)

⁽²⁾	Income taxes are based on a percentage of net income before tax for the individual reportable segment with the impact of the DTA Remeasurement Loss included in the Other segment.

15. Segment Reporting (Continued)

Summary of Core Earnings Adjustments to GAAP

	Years Ended December 31,
(Dollars in millions)	2020			2019			2018
Core Earnings net income	$	631		$	607		$	519
Core Earnings adjustments to GAAP:
Net impact of derivative accounting⁽¹⁾		(265	)		5			(90	)
Net impact of goodwill and acquired intangible assets⁽²⁾		(22	)		(30	)		(47	)
Net income tax effect⁽³⁾		68			15			13
Total Core Earnings adjustments to GAAP		(219	)		(10	)		(124	)
GAAP net income	$	412		$	597		$	395

⁽¹⁾

Derivative accounting: Core Earnings exclude periodic gains and losses that are caused by the mark-to-market valuations on derivatives that do not qualify for hedge accounting treatment under GAAP as well as the periodic mark-to-market gains and losses that are a result of ineffectiveness recognized related to effective hedges under GAAP. Under GAAP, for our derivatives that are held to maturity, the mark-to-market gain or loss over the life of the contract will equal $0 except for Floor Income Contracts where the mark-to-market gain will equal the amount for which we sold the contract. In our Core Earnings presentation, we recognize the economic effect of these hedges, which generally results in any net settlement cash paid or received being recognized ratably as an interest expense or revenue over the hedged item’s life.

⁽²⁾

Goodwill and acquired intangible assets: Our Core Earnings exclude goodwill and intangible asset impairment and amortization of acquired intangible assets.

⁽³⁾

Net tax effect: Such tax effect is based upon our Core Earnings effective tax rate for the year.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8924-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8981-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8721-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9031-108599

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8844-108599

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9038-108599

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
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-Paragraph 32
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8657-108599

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
-Paragraph 21
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8721-108599

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-URI http://asc.fasb.org/topic&trid=2134510

+ Details

Allowance for Loan Losses - Age Analysis of Past Due Loans Delinquencies (Parenthetical) (Detail) $ in Millions	Dec. 31, 2020 USD ($)
Private Education Loans - TDRs [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans premium (discount)	$ 200
Private Education Loans - Non-TDRs [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans premium (discount)	275
FFELP Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Loans premium (discount)	$ 497

Business Combinations, Goodwill and Acquired Intangible - Acquired Intangible Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Acquired Finite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, Cost Basis	$ 428	$ 428
Intangible assets subject to amortization, Accumulated Impairment and Amortization	(358)	(336)
Intangible assets subject to amortization, Net	70	92
Customer, Services and Lending Relationships [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, Cost Basis	262	262
Intangible assets subject to amortization, Accumulated Impairment and Amortization	(230)	(220)
Intangible assets subject to amortization, Net	32	42
Software and Technology [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, Cost Basis	114	114
Intangible assets subject to amortization, Accumulated Impairment and Amortization	(101)	(96)
Intangible assets subject to amortization, Net	13	18
Trade Names and Trademarks [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization, Cost Basis	52	52
Intangible assets subject to amortization, Accumulated Impairment and Amortization	(27)	(20)
Intangible assets subject to amortization, Net	$ 25	$ 32

Revenue from Contracts with Customers Accounted for in Accordance with ASC 606 - Summary of Disaggregation of Revenue from Contracts with Customers Accounted Under ASC 606 (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Total Revenue	$ 388	$ 391
Federal Government [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	62	91
Guarantor Agencies [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	38	52
Other Institutions [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	2	7
State and Local Government [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	122	83
Tolling Authorities [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	51	54
Hospitals and Other Healthcare Providers [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	113	104
Federal Education Loan Asset Recovery Services [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	84	133
Government Services [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	191	154
Healthcare Services [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	113	104
Federal Education Loans [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	84	133
Federal Education Loans [Member] \| Federal Government [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	44	74
Federal Education Loans [Member] \| Guarantor Agencies [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	38	52
Federal Education Loans [Member] \| Other Institutions [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	2	7
Federal Education Loans [Member] \| Federal Education Loan Asset Recovery Services [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	84	133
Business Processing [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	304	258
Business Processing [Member] \| Federal Government [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	18	17
Business Processing [Member] \| State and Local Government [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	122	83
Business Processing [Member] \| Tolling Authorities [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	51	54
Business Processing [Member] \| Hospitals and Other Healthcare Providers [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	113	104
Business Processing [Member] \| Government Services [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	191	154
Business Processing [Member] \| Healthcare Services [Member]
Disaggregation Of Revenue [Line Items]
Total Revenue	$ 113	$ 104

Business Combinations, Goodwill and Acquired Intangible - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Combinations [Abstract]
Amortization of acquired intangible assets	$ 21	$ 25	$ 31
2021	19
2022	15
2023	13
2024	10
After 2024	$ 13

Allowance for Loan Losses - Additional Information (Detail) - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Line Items]
Percentage of loans granted forbearance that migrated to TDR classification	72.00%	69.00%
Payment default period for TDRs	60 days past due
Interest Rate Reduction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
TDR loans, Unpaid Principal Balance	$ 948.0	$ 1.7

Borrowings - Additional Information (Detail) - USD ($)	12 Months Ended
Borrowings - Additional Information (Detail) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2015
Debt Instrument [Line Items]
Outstanding borrowings under facility	$ 83,945,000,000	$ 90,198,000,000
Issuance of unsecured debt	700,000,000	$ 0	$ 500,000,000
FFELP Loan ABCP Facilities [Member]
Debt Instrument [Line Items]
Outstanding borrowings under facility	2,500,000,000
Assets securing facility	2,600,000,000
Maximum unused capacity	506,000,000
Unencumbered Loans	$ 200,000,000
FFELP Loan ABCP Facilities [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Facility maturity date	2021-11
FFELP Loan ABCP Facilities [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Facility maturity date	2022-04
FFELP Loan \| Asset-backed Securities, Securitized Loans and Receivables [Member]
Debt Instrument [Line Items]
Outstanding borrowings under facility	$ 200,000,000
Amount of asset-backed securitization repurchase facility			$ 900,000,000
Private Education Loan ABCP Facilities [Member]
Debt Instrument [Line Items]
Outstanding borrowings under facility	2,600,000,000
Assets securing facility	2,900,000,000
Maximum unused capacity	2,200,000,000
Unencumbered Loans	$ 2,400,000,000
Private Education Loan ABCP Facilities [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Facility maturity date	2021-06
Private Education Loan ABCP Facilities [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Facility maturity date	2021-12
Private Education Loan Repurchase Facilities [Member] \| Asset-backed Securities, Securitized Loans and Receivables [Member]
Debt Instrument [Line Items]
Outstanding borrowings under facility	$ 1,200,000,000
Amount of asset-backed securitization repurchase facility				$ 4,300,000,000

Derivative Financial Instruments - Collateral Held and Pledged (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Collateral held:
Cash (obligation to return cash collateral is recorded in short-term borrowings)	$ 336	$ 337
Securities at fair value - on-balance sheet securitization derivatives (not recorded in financial statements)	78	69
Total collateral held	414	406
Derivative asset at fair value including accrued interest	351	282
Collateral pledged to others:
Cash (right to receive return of cash collateral is recorded in investments)	234	155
Total collateral pledged	234	155
Derivative liability at fair value including accrued interest and premium receivable	$ 504	$ 658

Earnings (Loss) per Common Share

12 Months Ended

Dec. 31, 2020

Earnings Per Share [Abstract]

Earnings (Loss) per Common Share

10. Earnings (Loss) per Common Share

Basic earnings (loss) per common share (EPS) are calculated using the weighted average number of shares of common stock outstanding during each period. A reconciliation of the numerators and denominators of the basic and diluted EPS calculations on a GAAP basis follows.

	Years Ended December 31,
(In millions, except per share data)	2020		2019		2018
Numerator:
Net income	$	412	$	597	$	395
Denominator:
Weighted average shares used to compute basic EPS		193		230		260
Effect of dilutive securities:
Dilutive effect of stock options, restricted stock, restricted stock units, performance stock units and Employee Stock Purchase Plan (ESPP)⁽¹⁾		2		3		4
Dilutive potential common shares⁽²⁾		2		3		4
Weighted average shares used to compute diluted EPS		195		233		264
Basic earnings per common share	$	2.14	$	2.59	$	1.52
Diluted earnings per common share	$	2.12	$	2.56	$	1.49

⁽¹⁾

Includes the potential dilutive effect of additional common shares that are issuable upon exercise of outstanding stock options, restricted stock, restricted stock units, performance stock units and the outstanding commitment to issue shares under applicable ESPPs, determined by the treasury stock method.

⁽²⁾	For the years ended December 31, 2020, 2019 and 2018, stock options covering approximately 2 million, 4 million and 6 million shares, respectively, were outstanding but not included in the computation of diluted earnings per share because they were anti-dilutive.

Fair Value Measurements - Included in Earnings (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Gains (losses) on derivative and hedging activities, net	$ 239	$ (50)	$ (414)
Gain (Losses) on Derivative Instruments [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Gains (losses) on derivative and hedging activities, net	8	10	(292)
Interest Expense [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Gains (losses) on derivative and hedging activities, net	$ 231	$ (60)	$ (122)

Allowance for Loan Losses - Loans Modified Accounts for TDR (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Modified loans	$ 264	$ 475	$ 596
Charge-offs	157	324	343
Payment default	$ 47	$ 109	$ 142

Commitments, Contingencies and Guarantees - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2016 Case	Dec. 31, 2020 USD ($)
Loss Contingencies [Line Items]
Number of cases filed \| Case	3
SLM BankCo [Member] \| Indemnification Matters [Member]
Loss Contingencies [Line Items]
Reserve for estimated amounts and costs incurred \| $		$ 0

Income Taxes - Summary of Changes in Unrecognized Tax Benefits (Parenthetical) (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 57.9	$ 53.6	$ 65.7	$ 57.4
Unrecognized tax benefits recognition impact on effective tax rate	$ 45.7

Business Combinations, Goodwill and Acquired Intangible

12 Months Ended

Dec. 31, 2020

Business Combinations [Abstract]

Business Combinations, Goodwill and Acquired Intangible

5. Business Combinations, Goodwill and Acquired Intangible

Goodwill

The following table summarizes our goodwill for our reporting units and reportable segments.

(Dollars in millions)	As of Dec. 31, 2020 and Dec. 31, 2019
Federal Education Loans reportable segment:
FFELP Loans	$	227
Federal Education Loan Servicing		13
Total		240
Consumer Lending reportable segment:
Private Education Loans		106
Private Education Refinance Loans		77
Total		183
Business Processing reportable segment:
Government Services		136
Healthcare Services		106
Total		242
Total goodwill	$	665

Interim Trigger Event Assessments

During 2020, COVID-19 created significant disruption in the U.S. economy and impacted the macroeconomic conditions which impact our reporting units with goodwill, the industry and markets in which these reporting units operate, their cost structures and, to some degree, their expected 2020 financial performance. As a result, we assessed whether a triggering event occurred as of September 30, 2020, June 30, 2020 and March 31, 2020.

We assessed relevant qualitative factors to determine whether it was “more-likely-than-not” that the fair value of an individual reporting unit was less than its carrying value. We considered the amount of excess fair values over the carrying values of each reporting unit as of October 1, 2019 when we last performed a quantitative goodwill impairment test. The concluded fair values of the reporting units at October 1, 2019 were substantially in excess of their carrying amounts. Additionally, fair values resulting from sensitivity analyses factoring in more conservative discount rates and growth rates for each reporting unit also yielded fair values in excess of the carrying values of each reporting unit.

Despite COVID-19, the outlook and associated long-term cash flow projections of our FFELP Loans, Private Education Loans-Legacy, and Federal Education Loan Servicing reporting units have not changed significantly since our 2019 assessment. For the Private Education Loan Refinance reporting unit, we considered origination volume and the demand for its refinance loan products as well as Navient’s strong liquidity position and ability to issue Private Education Loan ABS comprised entirely of the reporting unit’s refinance loans albeit at a higher cost of funds. For Government and Healthcare Services, we also considered the short and long-term outlook for these businesses including temporary stoppage of certain collection and processing activity and lower volume in the transportation business. We also considered that no contracts had been terminated due to COVID-19, and significant additional contracts were acquired in 2020 to implement programs under the CARES Act and perform contact tracing services. The revenue from these new contracts more than offset the decline in other revenue which occurred due to COVID-19. Based on these qualitative factors, we concluded that it was not “more-likely-than-not” that the fair value of an individual reporting unit was less than its carrying value as of September 30, 2020, June 30, 2020 and March 31, 2020. As a result, COVID-19 and its impact to Navient’s individual reporting units as we perceived them during each quarter did not constitute a triggering event. No further impairment testing was performed during interim quarters in 2020.

5. Business Combinations, Goodwill and Acquired Intangible (Continued)

Annual Goodwill Impairment Testing – October 1, 2020

We perform our goodwill impairment testing annually in the fourth quarter as of October 1. As part of the 2020 annual impairment testing associated with our FFELP Loans, Federal Education Loan Servicing, Private Education Loan-Legacy and Private Education Refinance Loans reporting units, we assessed relevant qualitative factors to determine whether it is “more-likely-than-not” that the fair value of an individual reporting unit is less than its carrying value. Consistent with the interim triggering events assessment performed during each quarter in 2020, we considered the amount of excess fair value for each reporting unit over their carrying values as of October 1, 2019 since the fair value of these reporting units were substantially in excess of their carrying amounts. The outlook and cash flows for the FFELP Loans, Private Education Loans-Legacy and Federal Education Loan Servicing reporting units have not changed significantly since our 2019 assessment despite COVID-19. Also consistent with the triggering events assessments we completed each quarter, for the Private Education Refinance Loans reporting unit, we considered current and expected future origination volume both of which increased since prior quarters and the improved demand for the reporting unit’s refinance loan products as well as Navient’s strong liquidity position and ability to issue Private Education Loan ABS comprised entirely of the reporting unit’s refinance loans. No goodwill was deemed impaired for these reporting units after assessing these relevant qualitative factors.

As part of our annual impairment testing associated with our Government Services and Healthcare Services reporting units, we retained a third-party appraisal firm to assist in the valuations required to perform a quantitative impairment test for these reporting units. No goodwill was deemed impaired in conjunction with these reporting units as a result of the quantitative impairment tests as the fair values of the reporting units were substantially greater than their respective carry values at October 1, 2020.

The income approach was the primary approach used to estimate the fair value of each reporting unit. The income approach measures the value of each reporting unit’s future economic benefit determined by its discounted cash flows derived from assumptions we believe a market participant would assume in an acquisition, principally projected financial information derived based on our long term projections and an assumed terminal growth rate. The projections used for purposes of the quantitative test are four-year projections that reflect the anticipated cash flow fluctuations of the respective reporting units.

Under our guidance, the third-party appraisal firm developed the discount rates for these reporting units incorporating such factors as the risk free rate, a market rate of return, a measure of volatility (Beta) and a company-specific and capital markets risk premium to adjust for volatility and uncertainty in the economy and to capture specific risk related to the respective reporting units. We considered whether an asset sale or an equity sale would be the most likely sale structure for each reporting unit and valued each reporting unit based on the more likely hypothetical scenario. The discount rates reflect market-based estimates of capital costs and are adjusted for our assessment of a market participant’s view with respect to execution, source concentration and other risks associated with the projected cash flows of the individual reporting units. We reviewed and approved the discount rates provided by the third-party appraiser including the factors incorporated to develop the discount rates for each reporting unit.

We and the third-party appraisal firm also considered a market approach to value the Government Services and Healthcare Services reporting units. Market-based multiples related primarily to revenue and EBITDA for comparable publicly traded companies and similar transactions were evaluated as an indicator of the value of the reporting units to assess the reasonableness of the estimated fair value derived from the income approach.

For each of our reporting units, we have also considered the current regulatory and legislative environment, the current economic environment which is heavily impacted by COVID-19, our 2020 earnings, 2021 expected earnings, market expectations regarding our stock price, and our market capitalization in relation to book equity. Although our market capitalization was less than our book equity during 2020, it was concluded that our market capitalization in relation to our book equity does not indicate impairment of our reporting units’ respective goodwill at December 31, 2020 as our market capitalization which has been impacted by market declines due to the COVID-19 pandemic, is not indicative of the value of our reporting units with goodwill on a standalone basis. If the regulatory environment changes such that it negatively impacts our reporting units and future economic conditions as a result of COVID-19 are significantly worse than what was assumed as a part of our annual impairment testing for each of our reporting units, specifically related to the severity and length of the downturn and subsequent recovery, goodwill attributed to our reporting units could be impaired in future periods.

5. Business Combinations, Goodwill and Acquired Intangible Assets (Continued)

Acquired Intangible Assets

Acquired intangible assets include the following:

	As of December 31, 2020							As of December 31, 2019
(Dollars in millions)	Cost Basis⁽¹⁾		Accumulated Impairment and Amortization⁽¹⁾⁽²⁾			Net		Cost Basis⁽¹⁾		Accumulated Impairment and Amortization⁽¹⁾⁽²⁾			Net
Customer, services and lending relationships	$	262	$	(230	)	$	32	$	262	$	(220	)	$	42
Software and technology		114		(101	)		13		114		(96	)		18
Trade names and trademarks		52		(27	)		25		52		(20	)		32
Total acquired intangible assets	$	428	$	(358	)	$	70	$	428	$	(336	)	$	92

⁽¹⁾

Accumulated impairment and amortization include impairment amounts only if the acquired intangible asset has been deemed partially impaired. When an acquired intangible asset is considered fully impaired and no longer in use, the cost basis and any accumulated amortization related to the asset is written off.

⁽²⁾

We recorded amortization of acquired intangible assets of $21 million, $25 million and $31 million in 2020, 2019 and 2018, respectively. We will continue to amortize our intangible assets with definite useful lives over their remaining estimated useful lives. We estimate amortization expense associated with these intangible assets will be $19 million, $15 million, $13 million, $10 million and $13 million in 2021, 2022, 2023, 2024 and after 2024, respectively.

Income Taxes - Reconciliations of Statutory U.S. Federal Income Tax Rates to Our Effective Tax Rate for Continuing Operations (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Statutory rate	21.00%	21.00%	21.00%
State tax, net of federal benefit	1.60%	1.40%	3.90%
Other, net		(0.50%)	0.30%
Effective tax rate	22.60%	21.90%	25.20%

Fair Value Measurements - Valuation of Financial Instruments that are Marked-to-Market on Recurring Basis (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	$ 357	$ 230
Derivative liabilities	(533)	(664)
Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	329	230
Derivative liabilities	(14)	(20)
Cross-Currency Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	28
Derivative liabilities	(322)	(575)
Floor Income Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	(197)	(68)
Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		(1)
Fair Value Measurements Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	357	230
Total	357	230
Derivative liabilities	(533)	(664)
Total	(533)	(664)
Fair Value Measurements Recurring [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	323	227
Total	323	227
Derivative liabilities	(197)	(68)
Total	(197)	(68)
Fair Value Measurements Recurring [Member] \| Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	34	3
Total	34	3
Derivative liabilities	(336)	(596)
Total	(336)	(596)
Fair Value Measurements Recurring [Member] \| Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	329	230
Derivative liabilities	(14)	(20)
Fair Value Measurements Recurring [Member] \| Interest Rate Swaps [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	323	227
Fair Value Measurements Recurring [Member] \| Interest Rate Swaps [Member] \| Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	6	3
Derivative liabilities	(14)	(20)
Fair Value Measurements Recurring [Member] \| Cross-Currency Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	28
Derivative liabilities	(322)	(575)
Fair Value Measurements Recurring [Member] \| Cross-Currency Interest Rate Swaps [Member] \| Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	28
Derivative liabilities	(322)	(575)
Fair Value Measurements Recurring [Member] \| Floor Income Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	(197)	(68)
Fair Value Measurements Recurring [Member] \| Floor Income Contracts [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	$ (197)	(68)
Fair Value Measurements Recurring [Member] \| Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		(1)
Fair Value Measurements Recurring [Member] \| Other [Member] \| Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		$ (1)

Income Taxes

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Income Taxes

13. Income Taxes

Reconciliations of the statutory U.S. federal income tax rates to our effective tax rate for continuing operations follow:

	Years Ended December 31,
	2020			2019			2018
Statutory rate		21.0	%		21.0	%		21.0	%
State tax, net of federal benefit		1.6			1.4			3.9
Other, net		—			(.5	)		.3
Effective tax rate		22.6	%		21.9	%		25.2	%

Income tax expense consists of:

	December 31,
(Dollars in millions)	2020			2019		2018
Current provision/(benefit):
Federal	$	98		$	78	$	71
State		14			11		13
Foreign		(1	)		—		3
Total current provision/(benefit)		111			89		87
Deferred provision/(benefit):
Federal		12			73		33
State		(3	)		3		13
Foreign		—			1		—
Total deferred provision/(benefit)		9			77		46
Provision for income tax expense/(benefit)	$	120		$	166	$	133

13. Income Taxes (Continued)

The tax effect of temporary differences that give rise to deferred tax assets and liabilities include the following:

	December 31,
(Dollars in millions)	2020		2019
Deferred tax assets:
Loan reserves	$	414	$	257
Market value adjustments on education loans, investments and derivatives		64		—
Education loan premiums and discounts, net		41		44
Operating loss and credit carryovers		14		17
Accrued expenses not currently deductible		22		16
Stock-based compensation plans		6		10
Other		22		21
Total deferred tax assets		583		365
Deferred tax liabilities:
Acquired intangible assets		16		17
Market value adjustments on education loans, investments and derivatives		—		13
Original issue discount on borrowings		11		10
Other		16		18
Total deferred tax liabilities		43		58
Net deferred tax assets	$	540	$	307

Included in operating loss and credit carryovers is a valuation allowance of $64 million and $60 million as of December 31, 2020 and 2019, respectively, against a portion of the Company’s federal and state deferred tax assets. The valuation allowance is primarily attributable to deferred tax assets for federal and state net operating loss carryovers and state IRC § 163(j) disallowed interest expense carryovers that management believes it is more likely than not will expire prior to being realized. The ultimate realization of the deferred tax assets is dependent upon the generation of future taxable income of the appropriate character (i.e. capital or ordinary) during the period in which the temporary differences become deductible. Factors generally considered by management include (but are not limited to): any changes in economic conditions, the scheduled reversals of deferred tax liabilities, and the history of positive taxable income available for net operating loss carrybacks in evaluating the realizability of the deferred tax assets.

The operating loss and credit carryovers consist of:

	December 31, 2020
(Dollars in millions)	Gross		Tax-Effected		Expiration	Corresponding Valuation Allowance⁽¹⁾		Operating Loss and Credit Carryovers
Federal operating loss carryovers	$	53	$	11	Begins in 2031	$	—	$	11
State operating loss carryovers		505		36	Begins in 2021		33		3
State IRC § 163(j) disallowed interest expense carryovers		1,907		29	Indefinite		29		—
Federal and State capital loss carryovers		10		2	Begins in 2021		2		—
			$	78		$	64	$	14

⁽¹⁾

13. Income Taxes (Continued)

Accounting for Uncertainty in Income Taxes

The following table summarizes changes in unrecognized tax benefits:

	December 31,
(Dollars in millions)	2020			2019			2018
Unrecognized tax benefits at beginning of year	$	53.6		$	65.7		$	57.4
Increases resulting from tax positions taken during a prior period		7.6			4.0			8.0
Decreases resulting from tax positions taken during a prior period		—			(3.8	)		(.3	)
Increases resulting from tax positions taken during the current period		3.5			1.9			3.8
Decreases related to settlements with taxing authorities		(.2	)		(11.1	)		(1.4	)
Increases related to settlements with taxing authorities		—			—			—
Reductions related to the lapse of statute of limitations		(6.6	)		(3.1	)		(1.8	)
Unrecognized tax benefits at end of year⁽¹⁾	$	57.9		$	53.6		$	65.7

The Company or one of its subsidiaries files income tax returns at the U.S. federal level, in most U.S. states, and various foreign jurisdictions. All periods prior to 2016 are closed for federal examinations purposes. Various combinations of subsidiaries, tax years, and jurisdictions remain open for review, subject to statute of limitations periods (typically 3 to 4 prior years). We do not expect the resolution of open audits to have a material impact on our unrecognized tax benefits.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References + Details

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Valuation allowance, Operating loss and credit carryovers	$ 64	$ 60
Minimum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Statute of limitation period for open tax reviews	3 years
Maximum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Statute of limitation period for open tax reviews	4 years

Borrowings

12 Months Ended

Dec. 31, 2020

Debt Disclosure [Abstract]

Borrowings

6. Borrowings

Borrowings consist of secured borrowings issued through our securitization program, borrowings through secured facilities, unsecured notes issued by us, and other interest-bearing liabilities related primarily to obligations to return cash collateral held.

The following table summarizes our borrowings.

	December 31, 2020												December 31, 2019
(Dollars in millions)	Short Term		Weighted Average Interest Rate⁽⁷⁾			Long Term		Weighted Average Interest Rate⁽⁷⁾			Total		Short Term		Weighted Average Interest Rate⁽⁷⁾			Long Term			Weighted Average Interest Rate⁽⁷⁾			Total
Unsecured borrowings:
Senior unsecured debt⁽¹⁾	$	677		6.61	%	$	7,714		6.19	%	$	8,391	$	1,052		6.45	%	$	8,461			6.30	%	$	9,513
Total unsecured borrowings		677		6.61			7,714		6.19			8,391		1,052		6.45			8,461			6.30			9,513
Secured borrowings:
FFELP Loan securitizations⁽²⁾⁽³⁾		—		—			54,697		.89			54,697		72		3.16			59,735			2.45			59,807
Private Education Loan securitizations⁽⁴⁾		960		2.68			13,891		2.04			14,851		2,120		4.14			11,430			3.12			13,550
FFELP Loan ABCP facilities		2,053		1.05			479		1.13			2,532		2,783		2.46			617			2.66			3,400
Private Education Loan ABCP facilities		2,582		1.46			—		—			2,582		2,114		2.76			1,513			3.31			3,627
Other⁽⁵⁾		337		.09			—		—			337		338		1.55			—			—			338
Total secured borrowings		5,932		1.44			69,067		1.12			74,999		7,427		2.99			73,295			2.58			80,722
Total before hedge accounting adjustments⁽⁶⁾		6,609		1.97			76,781		1.63			83,390		8,479		3.42			81,756			2.96			90,235
Hedge accounting adjustments		4		—			551		(.01	)		555		4		—			(41	)		—			(37	)
Total	$	6,613		1.97	%	$	77,332		1.62	%	$	83,945	$	8,483		3.42	%	$	81,715			2.96	%	$	90,198

⁽¹⁾	Includes principal amount of $678 million and $1.1 billion of short-term debt as of December 31, 2020 and 2019, respectively. Includes principal amount of $7.8 billion and $8.5 billion of long-term debt as of December 31, 2020 and 2019, respectively.

⁽²⁾

Includes $0 and $72 million of short-term debt related to the FFELP Loan ABS repurchase facilities (FFELP Loan Repurchase Facilities) as of December 31, 2020 and 2019, respectively. Includes $157 million and $231 million of long-term debt related to the FFELP Loan Repurchase Facilities as of December 31, 2020 and 2019, respectively.

⁽³⁾	Includes $3.6 billion and $4.0 billion of non-U.S. dollar-denominated debt as of December 31, 2020 and 2019, respectively, which has been hedged with swaps converting to U.S. dollars.

⁽⁴⁾

Includes $960 million and $2.1 billion of short-term debt related to the Private Education Loan ABS repurchase facilities (Private Education Loan Repurchase Facilities) as of December 31, 2020 and 2019, respectively. Includes $260 million and $194 million of long-term debt related to the Private Education Loan Repurchase Facilities as of December 31, 2020 and 2019, respectively.

⁽⁵⁾	“Other” primarily includes the obligation to return cash collateral held related to derivative exposure.

⁽⁶⁾	Includes $60.0 billion and $67.7 billion of long-term floating rate debt as of December 31, 2020 and 2019, respectively, and $16.8 billion and $14.0 billion of long-term fixed rate debt as of December 31, 2020 and 2019, respectively.

⁽⁷⁾	Weighted average interest rate is as of end of period.

6. Borrowings (Continued)

As of December 31, 2020, the expected maturities of our long-term borrowings are shown in the following table.

	Expected Maturity
(Dollars in millions)	Senior Unsecured Debt		Secured Borrowings⁽¹⁾			Total⁽²⁾
Year of Maturity
2021	$	—	$	6,792		$	6,792
2022		1,746		7,150			8,896
2023		1,506		6,035			7,541
2024		1,349		5,756			7,105
2025		550		5,522			6,072
2026-2043		2,563		37,812			40,375
		7,714		69,067			76,781
Hedge accounting adjustments		718		(167	)		551
Total	$	8,432	$	68,900		$	77,332

⁽¹⁾

We view our securitization trust debt as long-term based on the contractual maturity dates which range from 2021 to 2083. However, we have projected the expected principal paydowns based on our current estimates regarding the securitized loans’ prepayment speeds for purposes of this disclosure to better reflect how we expect this debt to be paid down over time. The projected principal paydowns in year 2021 include $6.8 billion related to the securitization trust debt.

⁽²⁾

The aggregate principal amount of debt that matures in each period is $6.8 billion in 2021, $9.0 billion in 2022, $7.6 billion in 2023, $7.2 billion in 2024, $6.1 billion in 2025 and $40.7 billion in 2026-2043.

Variable Interest Entities

We consolidated the following financing VIEs as of December 31, 2020 and 2019, as we are the primary beneficiary. As a result, these VIEs are accounted for as secured borrowings.

	December 31, 2020
	Debt Outstanding								Carrying Amount of Assets Securing Debt Outstanding
(Dollars in millions)	Short Term		Long Term			Total			Loans		Cash		Other Assets, Net			Total
Secured Borrowings — VIEs:
FFELP Loan securitizations	$	—	$	54,697		$	54,697		$	55,535	$	1,606	$	1,438		$	58,579
Private Education Loan securitizations		960		13,891			14,851			15,823		606		187			16,616
FFELP Loan ABCP facilities		2,053		479			2,532			2,533		36		76			2,645
Private Education Loan ABCP facilities		2,582		—			2,582			2,835		74		27			2,936
Total before hedge accounting adjustments		5,595		69,067			74,662			76,726		2,322		1,728			80,776
Hedge accounting adjustments		—		(167	)		(167	)		—		—		(308	)		(308	)
Total	$	5,595	$	68,900		$	74,495		$	76,726	$	2,322	$	1,420		$	80,468

	December 31, 2019
	Debt Outstanding								Carrying Amount of Assets Securing Debt Outstanding
(Dollars in millions)	Short Term		Long Term			Total			Loans		Cash		Other Assets, Net			Total
Secured Borrowings — VIEs:
FFELP Loan securitizations	$	72	$	59,735		$	59,807		$	60,834	$	1,833	$	1,400		$	64,067
Private Education Loan securitizations		2,120		11,430			13,550			15,412		509		152			16,073
FFELP Loan ABCP facilities		2,783		617			3,400			3,421		63		102			3,586
Private Education Loan ABCP facilities		2,114		1,513			3,627			4,197		101		28			4,326
Total before hedge accounting adjustments		7,089		73,295			80,384			83,864		2,506		1,682			88,052
Hedge accounting adjustments		—		(439	)		(439	)		—		—		(593	)		(593	)
Total	$	7,089	$	72,856		$	79,945		$	83,864	$	2,506	$	1,089		$	87,459

6. Borrowings (Continued)

Secured Facilities and Unsecured Debt

FFELP Loan ABCP Facilities

We have various ABCP borrowing facilities that we use to finance our FFELP Loans. Liquidity is available under these secured credit facilities to the extent we have eligible collateral and available capacity. The maximum borrowing capacity under these facilities will vary and is subject to each agreement’s borrowing conditions. These include but are not limited to the facility’s size, current usage and the availability and fair value of qualifying unencumbered FFELP Loan collateral. Our borrowings under these facilities are non-recourse. The maturity dates on these facilities range from November 2021 to April 2022. The interest rate on certain facilities can increase under certain circumstances. The facilities are subject to termination under certain circumstances. As of December 31, 2020, there was approximately $2.5 billion outstanding under these facilities, with approximately $2.6 billion of assets securing these facilities. As of December 31, 2020, the maximum unused capacity under these facilities was $506 million and we had $0.2 billion of unencumbered FFELP Loans.

FFELP Loan Repurchase Facilities

In 2018, we closed a $0.9 billion FFELP Loan Repurchase Facility that provides liquidity for the acquisition of certain Navient-sponsored auction rate securities. Borrowings under the facility are secured by the auction rate securities. The lenders also have unsecured recourse to Navient Corporation as guarantor for any shortfall in amounts payable. Because the facility is secured by Navient-sponsored instruments issued in previous securitizations, we show the debt as part of FFELP Loan securitizations in the various borrowing tables above. As of December 31, 2020, there was approximately $0.2 billion outstanding under this facility.

Private Education Loan ABCP Facilities

We have various ABCP borrowing facilities that we use to finance our Private Education Loans. Liquidity is available under these secured credit facilities to the extent we have eligible collateral and available capacity. The maximum borrowing capacity under these facilities will vary and is subject to each agreement’s borrowing conditions. These include but are not limited to the facility’s size, current usage and the availability and fair value of qualifying unencumbered Private Education Loan collateral. Our borrowings under these facilities are non-recourse. The maturity dates on these facilities range from June 2021 to December 2021. The interest rate on certain facilities can increase under certain circumstances. The facilities are subject to termination under certain circumstances. As of December 31, 2020, there was approximately $2.6 billion outstanding under these facilities, with approximately $2.9 billion of assets securing these facilities. As of December 31, 2020, the maximum unused capacity under these facilities was $2.2 billion and we had $2.4 billion of unencumbered Private Education Loans.

Private Education Loan Repurchase Facilities

Since the fourth quarter of 2015, we have closed on $4.3 billion of Private Education Loan Repurchase Facilities. These repurchase facilities are collateralized by Residual Interests in previously issued Private Education Loan ABS trusts. The lenders also have unsecured recourse to Navient Corporation as guarantor for any shortfall in amounts payable. Because these facilities are secured by the Residual Interests in previous securitizations, we show the debt as part of Private Education Loan securitizations in the various borrowing tables above. As of December 31, 2020, there was approximately $1.2 billion outstanding under these facilities.

Senior Unsecured Debt

We issued $700 million, $0 and $500 million of unsecured debt in 2020, 2019 and 2018, respectively.

Debt Repurchases

The following table summarizes activity related to our senior unsecured debt repurchases.

	Years Ended December 31,
(Dollars in millions)	2020			2019		2018
Debt principal repurchased	$	768		$	1,184	$	2,809
Gains (losses) on debt repurchases	$	(6	)	$	45	$	19

Stockholders' Equity - Common Share Repurchases, Issuances and Dividends Paid (Parenthetical) (Detail) - USD ($) $ in Millions	Oct. 31, 2019	Sep. 30, 2018
Equity [Abstract]
Authorized share repurchased program amount	$ 1,000	$ 500

Business Combinations, Goodwill and Acquired Intangible - Summary of Goodwill for Each Reporting Units and Reportable Segments (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Line Items]
Goodwill	$ 665	$ 665
Federal Education Loans [Member]
Goodwill [Line Items]
Goodwill	240	240
Federal Education Loans [Member] \| FFELP Loans [Member]
Goodwill [Line Items]
Goodwill	227	227
Federal Education Loans [Member] \| Federal Education Loan Servicing [Member]
Goodwill [Line Items]
Goodwill	13	13
Consumer Lending Segment [Member]
Goodwill [Line Items]
Goodwill	183	183
Consumer Lending Segment [Member] \| Private Education Loans [Member]
Goodwill [Line Items]
Goodwill	106	106
Consumer Lending Segment [Member] \| Private Education Refinance Loans [Member]
Goodwill [Line Items]
Goodwill	77	77
Business Processing [Member]
Goodwill [Line Items]
Goodwill	242	242
Business Processing [Member] \| Government Services [Member]
Goodwill [Line Items]
Goodwill	136	136
Business Processing [Member] \| Healthcare Services [Member]
Goodwill [Line Items]
Goodwill	$ 106	$ 106

Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions		12 Months Ended
	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Summary Of Significant Accounting Policies [Line Items]
Loans receivable, carrying amount			$ 88,013	$ 96,014
Allowance for loans losses		$ 1,377	1,112	1,286	$ 1,367
Reduction in equity (retained earnings), net of tax resulted from current expected credit losses		(3,331)	(3,664)
Provisions for loan losses		$ 155	258	370
Percentage of threshold		50.00%
Goodwill impaired method for fair value determination		We complete a goodwill impairment analysis which may be a qualitative or a quantitative analysis depending on the facts and circumstances associated with the reporting unit. In conjunction with a qualitative impairment analysis, we assess relevant qualitative factors to determine whether it is “more-likely-than-not” that the fair value of a reporting unit is less than its carrying amount. The “more-likely-than-not” threshold is defined as having a likelihood of more than 50%. If, based on first assessing impairment utilizing a qualitative approach, we determine it is “more-likely-than-not” that the fair value of the reporting unit is less than its carrying amount, we will also complete a quantitative impairment analysis. In conjunction with a quantitative impairment analysis, we compare the fair value of the reporting unit to the reporting unit’s carrying value, including goodwill. If the carrying value of the reporting unit exceeds the fair value, goodwill is impaired in an amount equal to the amount by which the carrying value exceeds the fair value of the reporting unit not to exceed the goodwill amount attributed to the reporting unit.
Option to exercise clean-up call and purchase education loans from trust of original loan balance		10% or less of the original loan balance
Percentage of trust's asset balance needed to trigger clean-up call		10.00%
Option to purchase education loan of the trust's initial pool balance		up to 10% of the trust’s initial pool balance
Assets		$ 87,412	94,903
Description of post employment benefits		The Company administers the Navient Corporation Employee Severance Plan and the Navient Corporation Executive Severance Plan for Senior Officers (collectively, the Severance Plan). The Severance Plan provides severance benefits in the event of termination of the Company’s full-time employees and part-time employees who work at least 24 hours per week.
Restructuring/other reorganization expenses		$ 9	6	13
Securitization Trust [Member]
Summary Of Significant Accounting Policies [Line Items]
Assets		$ 13
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of aggregate education loan to purchase		10.00%
COVID-19’s [Member]
Summary Of Significant Accounting Policies [Line Items]
Provisions for loan losses		$ 155
FFELP Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Loans receivable, carrying amount		58,572	64,094	71,730
Allowance for loans losses		288	64	76	60
Provisions for loan losses		$ 13	30	70
Default period of principal amount of loans		2 years
FFELP Loans [Member] \| Loans Disbursed after October 1, 1993, and before July 1, 2006 [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage reimbursement on all qualifying default claims period		98.00%
FFELP Loans [Member] \| Loans Disbursed on or after July 1, 2006 [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage reimbursement on all qualifying default claims period		97.00%
FFELP Loans [Member] \| Loans Disbursed prior to October 1, 1993 [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage reimbursement on all qualifying default claims period		100.00%
Private Education Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Loans receivable, carrying amount		$ 22,168	23,910	24,205
Allowance for loans losses		1,089	1,048	1,201	$ 1,297
Provisions for loan losses		$ 142	226	$ 299
Private Education Loans [Member] \| Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Delinquency period (in days)		212 days
Private Education Loans [Member] \| Loans Receivable For Partially Charged Off Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Receivable for partially charged-off loans			588
Credit Deteriorated Portfolio [Member] \| Private Education Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Loans receivable, carrying amount	$ 70
Allowance for loans losses	43
ASU 2016-13 [Member]
Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 01, 2020
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]		false
Allowance for loans losses	1,369		1,369
ASU 2016-13 [Member] \| FFELP Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Allowance for loans losses	324		324
ASU 2016-13 [Member] \| Private Education Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Allowance for loans losses	1,045		$ 1,045
ASU 2016-13 [Member] \| Credit Deteriorated Portfolio [Member]
Summary Of Significant Accounting Policies [Line Items]
Provisions for loan losses	43
ASU 2016-13 [Member] \| Credit Deteriorated Portfolio [Member] \| Private Education Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Provisions for loan losses	43
ASU 2016-13 [Member] \| Non-PCD Portfolio [Member]
Summary Of Significant Accounting Policies [Line Items]
Provisions for loan losses	802
ASU 2016-13 [Member] \| Non-PCD Portfolio [Member] \| Cumulative Effect Period of Adoption Adjustment [Member]
Summary Of Significant Accounting Policies [Line Items]
Reduction in equity (retained earnings), net of tax resulted from current expected credit losses	620
ASU 2016-13 [Member] \| Non-PCD Portfolio [Member] \| FFELP Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Provisions for loan losses	260
ASU 2016-13 [Member] \| Non-PCD Portfolio [Member] \| Private Education Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Provisions for loan losses	542
ASU 2016-13 [Member] \| Non-PCD Portfolio [Member] \| Private Education Loans [Member] \| FFELP Loans [Member] \| Cumulative Effect Period of Adoption Adjustment [Member]
Summary Of Significant Accounting Policies [Line Items]
Allowance for loans losses	802
ASU 2016-13 [Member] \| Non-PCD Portfolio [Member] \| Private Education Loans [Member] \| Equity [Member] \| FFELP Loans [Member] \| Cumulative Effect Period of Adoption Adjustment [Member]
Summary Of Significant Accounting Policies [Line Items]
Reduction in equity (retained earnings), net of tax resulted from current expected credit losses	$ 620
ASU 2017-04 [Member]
Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 01, 2020

Segment Reporting - Core Earnings Adjustments to GAAP (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2020 USD ($)
Segment Reporting [Abstract]
Amount that will be equal to mark-to-market gain or loss over the life of the contract	$ 0

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2020

Fair Value Disclosures [Abstract]

Valuation of Financial Instruments that are Marked-to-Market on Recurring Basis

11. Fair Value Measurements (Continued)

The following table summarizes the valuation of our financial instruments that are marked-to-market on a recurring basis. During 2020 and 2019, there were no significant transfers of financial instruments between levels.

	Fair Value Measurements on a Recurring Basis
	December 31, 2020											December 31, 2019
(Dollars in millions)	Level 1		Level 2			Level 3			Total			Level 1		Level 2			Level 3			Total
Assets
Derivative instruments:⁽¹⁾
Interest rate swaps		—		323			6			329			—		227			3			230
Cross-currency interest rate swaps		—		—			28			28			—		—			—			—
Total derivative assets⁽²⁾		—		323			34			357			—		227			3			230
Total	$	—	$	323		$	34		$	357		$	—	$	227		$	3		$	230
Liabilities⁽³⁾
Derivative instruments⁽¹⁾
Interest rate swaps	$	—	$	—		$	(14	)	$	(14	)	$	—	$	—		$	(20	)	$	(20	)
Floor Income Contracts		—		(197	)		—			(197	)		—		(68	)		—			(68	)
Cross-currency interest rate swaps		—		—			(322	)		(322	)		—		—			(575	)		(575	)
Other		—		—			—			—			—		—			(1	)		(1	)
Total derivative liabilities⁽²⁾		—		(197	)		(336	)		(533	)		—		(68	)		(596	)		(664	)
Total	$	—	$	(197	)	$	(336	)	$	(533	)	$	—	$	(68	)	$	(596	)	$	(664	)

⁽¹⁾	Fair value of derivative instruments excludes accrued interest and the value of collateral.

⁽²⁾	See “Note 7 — Derivative Financial Instruments” for a reconciliation of gross positions without the impact of master netting agreements to the balance sheet classification.

⁽³⁾	Borrowings which are the hedged item in a fair value hedge relationship and which are adjusted for changes in value due to benchmark interest rates only are not carried at full fair value and not reflected in this table.

Change in Balance Sheet Carrying Value Associated with Level 3 Financial Instruments Carried at Fair Value on Recurring Basis

11. Fair Value Measurements (Continued)

The following tables summarize the change in balance sheet carrying value associated with level 3 financial instruments carried at fair value on a recurring basis.

	Year Ended December 31, 2020
	Derivative Instruments
(Dollars in millions)	Interest Rate Swaps			Cross Currency Interest Rate Swaps			Other			Total Derivative Instruments
Balance, beginning of period	$	(17	)	$	(575	)	$	(1	)	$	(593	)
Total gains/(losses):
Included in earnings⁽¹⁾		8			231			—			239
Included in other comprehensive income		—			—			—			—
Settlements		1			50			1			52
Transfers in and/or out of level 3		—			—			—			—
Balance, end of period	$	(8	)	$	(294	)	$	—		$	(302	)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date⁽²⁾	$	5		$	273		$	1		$	279

	Year Ended December 31, 2019
	Derivative Instruments
(Dollars in millions)	Interest Rate Swaps			Cross Currency Interest Rate Swaps			Other			Total Derivative Instruments
Balance, beginning of period	$	(27	)	$	(633	)	$	(4	)	$	(664	)
Total gains/(losses):
Included in earnings⁽¹⁾		8			(60	)		2			(50	)
Included in other comprehensive income		—			—			—			—
Settlements		2			118			1			121
Transfers in and/or out of level 3		—			—			—			—
Balance, end of period	$	(17	)	$	(575	)	$	(1	)	$	(593	)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date⁽²⁾	$	9		$	58		$	3		$	70

	Year Ended December 31, 2018
	Derivative Instruments
(Dollars in millions)	Interest Rate Swaps			Cross Currency Interest Rate Swaps			Other			Total Derivative Instruments
Balance, beginning of period	$	(41	)	$	(322	)	$	(18	)	$	(381	)
Total gains/(losses):
Included in earnings⁽¹⁾		11			(433	)		8			(414	)
Included in other comprehensive income		—			—			—			—
Settlements		3			122			6			131
Transfers in and/or out of level 3		—			—			—			—
Balance, end of period	$	(27	)	$	(633	)	$	(4	)	$	(664	)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date⁽²⁾	$	13		$	(284	)	$	14		$	(257	)

⁽¹⁾

“Included in earnings” is comprised of the following amounts recorded in the specified line item in the consolidated statements of income:

Included in Earnings

	Years Ended December 31,
(Dollars in millions)	2020		2019			2018
Gains (losses) on derivative and hedging activities, net	$	8	$	10		$	(292	)
Interest expense		231		(60	)		(122	)
Total	$	239	$	(50	)	$	(414	)

⁽²⁾

Recorded in “gains (losses) on derivative and hedging activities, net” in the consolidated statements of income.

Unobservable Data Used in Recurring Valuations of Level 3

11. Fair Value Measurements (Continued)

The following table presents the significant inputs that are unobservable or from inactive markets used in the recurring valuations of the level 3 financial instruments detailed above.

(Dollars in millions)	Fair Value at December 31, 2020			Valuation Technique	Input	Range and Weighted Average
Derivatives
Prime/LIBOR basis swaps	$	(8	)	Discounted cash flow	Constant Prepayment Rate	9%
					Bid/ask adjustment to discount rate	.08%
Cross-currency interest rate swaps		(294	)	Discounted cash flow	Constant Prepayment Rate	5%
Other		—
Total	$	(302	)

Fair Values of Financial Assets and Liabilities, Including Derivative Financial Instruments

The following table summarizes the fair values of our financial assets and liabilities, including derivative financial instruments.

	December 31, 2020									December 31, 2019
(Dollars in millions)	Fair Value			Carrying Value			Difference			Fair Value			Carrying Value			Difference
Earning assets
FFELP Loans	$	59,117		$	58,284		$	833		$	64,478		$	64,575		$	(97	)
Private Education Loans		22,462			21,079			1,383			22,984			22,245			739
Cash and investments		3,822			3,822			—			3,992			3,992			—
Total earning assets		85,401			83,185			2,216			91,454			90,812			642
Interest-bearing liabilities
Short-term borrowings		6,626			6,613			(13	)		8,498			8,483			(15	)
Long-term borrowings		76,719			77,332			613			81,317			81,715			398
Total interest-bearing liabilities		83,345			83,945			600			89,815			90,198			383
Derivative financial instruments
Floor Income Contracts		(197	)		(197	)		—			(68	)		(68	)		—
Interest rate swaps		315			315			—			210			210			—
Cross-currency interest rate swaps		(294	)		(294	)		—			(575	)		(575	)		—
Other		—			—			—			(1	)		(1	)		—
Excess of net asset fair value over carrying value⁽¹⁾							$	2,816								$	1,025

⁽¹⁾

$371 million of this excess as of December 31, 2020 is a result of adjusting the Company’s $8.4 billion senior unsecured debt down to fair value compared to such adjustment being a $56 million increase as of December 31, 2019. This change in fair value is primarily a result of wider credit spreads as of December 31, 2020 as a result of COVID-19.

Fair Value Measurements - Unobservable Data Used in Recurring Valuations of Level 3 (Detail) $ in Millions	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Interest Rate Swaps [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivative financial instruments, Fair Value	$ 315	$ 210
Cross-Currency Interest Rate Swaps [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivative financial instruments, Fair Value	(294)	(575)
Other [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivative financial instruments, Fair Value		$ (1)
Level 3 [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivative financial instruments, Fair Value	(302)
Level 3 [Member] \| Cross-Currency Interest Rate Swaps [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivative financial instruments, Fair Value	$ (294)
Derivative Asset (Liability) Net, Valuation Technique [Extensible List]	us-gaap:ValuationTechniqueDiscountedCashFlowMember
Derivatives	0.05
Derivative Asset (Liability) Net, Measurement Input [Extensible List]	us-gaap:MeasurementInputConstantPrepaymentRateMember
Level 3 [Member] \| Prime/LIBOR Basis Swaps [Member] \| Interest Rate Swaps [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivative financial instruments, Fair Value	$ (8)
Derivative Asset (Liability) Net, Valuation Technique [Extensible List]	us-gaap:ValuationTechniqueDiscountedCashFlowMember
Level 3 [Member] \| Prime/LIBOR Basis Swaps [Member] \| Interest Rate Swaps [Member] \| Constant Prepayment Rate [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivatives	0.09
Level 3 [Member] \| Prime/LIBOR Basis Swaps [Member] \| Interest Rate Swaps [Member] \| Bid/ask adjustment to discount rate [Member]
Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivatives	0.0008

Segment Reporting - Core Earnings Adjustments to GAAP (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Adjustments Required To Reconcile Core Earnings [Line Items]
Net income (loss)	$ 412	$ 597	$ 395
Net income tax effect	(120)	(166)	(133)
Operating Segments [Member]
Adjustments Required To Reconcile Core Earnings [Line Items]
Net income (loss)	631	607	519
Net income tax effect	(188)	(181)	(146)
Total Adjustments [Member] \| Adjustments [Member]
Adjustments Required To Reconcile Core Earnings [Line Items]
Net income (loss)	(219)	(10)	(124)
Core Earnings adjustments to GAAP	(287)	(25)	(137)
Net income tax effect	68	15	13
Net Impact of Derivative Accounting [Member] \| Total Adjustments [Member] \| Adjustments [Member]
Adjustments Required To Reconcile Core Earnings [Line Items]
Core Earnings adjustments to GAAP	(265)	5	(90)
Net Impact of Goodwill and Acquired Intangible Assets [Member] \| Total Adjustments [Member] \| Adjustments [Member]
Adjustments Required To Reconcile Core Earnings [Line Items]
Core Earnings adjustments to GAAP	$ (22)	$ (30)	$ (47)

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

Segment Reporting - Segment Results and Reconciliations to GAAP (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest income:
Cash and investments	$ 16	$ 93	$ 97
Total interest income	3,298	4,673	4,908
Total interest expense	2,046	3,488	3,668
Net interest income	1,252	1,185	1,240
Less: provisions for loan losses	155	258	370
Net interest income after provisions for loan losses	1,097	927	870
Other income (loss):
Servicing revenue	214	240	274
Asset recovery and business processing revenue	458	488	430
Other income (loss)	(236)	67	(21)
Gains on sales of loans		16
Gains (losses) on debt repurchases	(6)	45	19
Total other income	430	856	702
Expenses:
Direct operating expenses	687	730	696
Unallocated shared services expenses	277	254	288
Total operating expenses	964	984	984
Goodwill and acquired intangible asset impairment and amortization	22	30	47
Restructuring/other reorganization expenses	9	6	13
Total expenses	995	1,020	1,044
Income before income tax expense	532	763	528
Income tax expense (benefit)	120	166	133
Net income	412	597	395
Operating Segments [Member]
Interest income:
Cash and investments	16	93	97
Total interest income	3,274	4,733	4,961
Total interest expense	2,013	3,517	3,672
Net interest income	1,261	1,216	1,289
Less: provisions for loan losses	155	258	370
Net interest income after provisions for loan losses	1,106	958	919
Other income (loss):
Servicing revenue	214	240	274
Asset recovery and business processing revenue	458	488	430
Other income (loss)	20	43	30
Gains on sales of loans		16
Gains (losses) on debt repurchases	(6)	33	9
Total other income	686	820	743
Expenses:
Direct operating expenses	687	730	696
Unallocated shared services expenses	277	254	288
Total operating expenses	964	984	984
Restructuring/other reorganization expenses	9	6	13
Total expenses	973	990	997
Income before income tax expense	819	788	665
Income tax expense (benefit)	188	181	146
Net income	631	607	519
Operating Segments [Member] \| Federal Education Loans [Member]
Interest income:
Cash and investments	7	50	46
Total interest income	1,820	2,958	3,130
Total interest expense	1,194	2,376	2,467
Net interest income	626	582	663
Less: provisions for loan losses	13	30	70
Net interest income after provisions for loan losses	613	552	593
Other income (loss):
Servicing revenue	208	229	262
Asset recovery and business processing revenue	154	230	163
Other income (loss)	9	28	24
Total other income	371	487	449
Expenses:
Direct operating expenses	287	359	298
Total operating expenses	287	359	298
Total expenses	287	359	298
Income before income tax expense	697	680	744
Income tax expense (benefit)	160	155	164
Net income	537	525	580
Operating Segments [Member] \| Consumer Lending [Member]
Interest income:
Cash and investments	3	16	13
Total interest income	1,448	1,748	1,793
Total interest expense	699	980	1,013
Net interest income	749	768	780
Less: provisions for loan losses	142	228	300
Net interest income after provisions for loan losses	607	540	480
Other income (loss):
Servicing revenue	6	11	12
Other income (loss)		1
Gains on sales of loans		16
Total other income	6	28	12
Expenses:
Direct operating expenses	146	156	169
Total operating expenses	146	156	169
Total expenses	146	156	169
Income before income tax expense	467	412	323
Income tax expense (benefit)	107	96	71
Net income	360	316	252
Operating Segments [Member] \| Business Processing [Member]
Other income (loss):
Asset recovery and business processing revenue	304	258	267
Total other income	304	258	267
Expenses:
Direct operating expenses	254	215	229
Total operating expenses	254	215	229
Total expenses	254	215	229
Income before income tax expense	50	43	38
Income tax expense (benefit)	11	10	8
Net income	39	33	30
Operating Segments [Member] \| Other Segment [Member]
Interest income:
Cash and investments	6	27	38
Total interest income	6	27	38
Total interest expense	120	161	192
Net interest income	(114)	(134)	(154)
Net interest income after provisions for loan losses	(114)	(134)	(154)
Other income (loss):
Other income (loss)	11	14	6
Gains (losses) on debt repurchases	(6)	33	9
Total other income	5	47	15
Expenses:
Unallocated shared services expenses	277	254	288
Total operating expenses	277	254	288
Restructuring/other reorganization expenses	9	6	13
Total expenses	286	260	301
Income before income tax expense	(395)	(347)	(440)
Income tax expense (benefit)	(90)	(80)	(97)
Net income	(305)	(267)	(343)
Adjustments [Member] \| Reclassifications [Member]
Interest income:
Total interest income	79	8	17
Total interest expense	39	6	8
Net interest income	40	2	9
Net interest income after provisions for loan losses	40	2	9
Other income (loss):
Other income (loss)	(40)	(41)	(22)
Gains (losses) on debt repurchases		39	13
Total other income	(40)	(2)	(9)
Adjustments [Member] \| Additions (Subtractions) [Member]
Interest income:
Total interest income	(55)	(68)	(70)
Total interest expense	(6)	(35)	(12)
Net interest income	(49)	(33)	(58)
Net interest income after provisions for loan losses	(49)	(33)	(58)
Other income (loss):
Other income (loss)	(216)	65	(29)
Gains (losses) on debt repurchases		(27)	(3)
Total other income	(216)	38	(32)
Expenses:
Goodwill and acquired intangible asset impairment and amortization	22	30	47
Total expenses	22	30	47
Income before income tax expense	(287)	(25)	(137)
Income tax expense (benefit)	(68)	(15)	(13)
Net income	(219)	(10)	(124)
Adjustments [Member] \| Total Adjustments [Member]
Interest income:
Total interest income	24	(60)	(53)
Total interest expense	33	(29)	(4)
Net interest income	(9)	(31)	(49)
Net interest income after provisions for loan losses	(9)	(31)	(49)
Other income (loss):
Other income (loss)	(256)	24	(51)
Gains (losses) on debt repurchases		12	10
Total other income	(256)	36	(41)
Expenses:
Goodwill and acquired intangible asset impairment and amortization	22	30	47
Total expenses	22	30	47
Income before income tax expense	(287)	(25)	(137)
Income tax expense (benefit)	(68)	(15)	(13)
Net income	(219)	(10)	(124)
Education Loan Portfolio [Member]
Interest income:
Total interest income	3,282	4,578	4,805
Education Loan Portfolio [Member] \| Operating Segments [Member]
Interest income:
Total interest income	3,258	4,638	4,858
Education Loan Portfolio [Member] \| Operating Segments [Member] \| Federal Education Loans [Member]
Interest income:
Total interest income	1,813	2,907	3,080
Education Loan Portfolio [Member] \| Operating Segments [Member] \| Consumer Lending [Member]
Interest income:
Total interest income	1,445	1,731	1,778
Education Loan Portfolio [Member] \| Adjustments [Member] \| Reclassifications [Member]
Interest income:
Total interest income	79	8	17
Education Loan Portfolio [Member] \| Adjustments [Member] \| Additions (Subtractions) [Member]
Interest income:
Total interest income	(55)	(68)	(70)
Education Loan Portfolio [Member] \| Adjustments [Member] \| Total Adjustments [Member]
Interest income:
Total interest income	$ 24	(60)	(53)
Other Loans [Member]
Interest income:
Total interest income		2	6
Other Loans [Member] \| Operating Segments [Member]
Interest income:
Total interest income		2	6
Other Loans [Member] \| Operating Segments [Member] \| Federal Education Loans [Member]
Interest income:
Total interest income		1	4
Other Loans [Member] \| Operating Segments [Member] \| Consumer Lending [Member]
Interest income:
Total interest income		$ 1	$ 2

Significant Accounting Policies - Summary of Translation Adjustments in Connection with Adopting CECL (Parenthetical) (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Reduction in equity (retained earnings), net of tax resulted from current expected credit losses	$ (3,331)		$ (3,664)
ASU 2016-13 [Member] \| Non-PCD Portfolio [Member] \| Cumulative Effect Period of Adoption Adjustment [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Reduction in equity (retained earnings), net of tax resulted from current expected credit losses		$ 620

Document and Entity Information - USD ($) $ in Billions	12 Months Ended
Document and Entity Information - USD ($) $ in Billions	Dec. 31, 2020	Jan. 31, 2021	Jun. 30, 2020
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Registrant Name	Navient Corporation
Entity Central Index Key	0001593538
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		183,771,633
Entity Public Float			$ 1.3
Entity File Number	001-36228
Entity Tax Identification Number	46-4054283
Entity Address, Address Line One	123 Justison Street
Entity Address, City or Town	Wilmington
Entity Address, State or Province	DE
Entity Address, Postal Zip Code	19801
City Area Code	(302)
Local Phone Number	283-8000
Entity Interactive Data Current	Yes
Entity Incorporation, State or Country Code	DE
Document Annual Report	true
Document Transition Report	false
Documents Incorporated by Reference	Portions of the proxy statement (the “2021 Proxy Statement”) relating to the Registrant’s 2021 Annual Meeting of Shareholders, to be filed no later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K, are incorporated by reference into Part III of this Annual Report on Form 10-K.
Common Stock Par Value. 01 Per Share [Member]
Document Information [Line Items]
Title of 12(b) Security	Common stock, par value $.01 per share
Trading Symbol	NAVI
Security Exchange Name	NASDAQ
Senior Notes Due December 15, 2043 [Member]
Document Information [Line Items]
Title of 12(b) Security	6% Senior Notes due December 15, 2043
Trading Symbol	JSM
Security Exchange Name	NASDAQ

Other Assets (Tables)

12 Months Ended

Dec. 31, 2020

Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]

Schedule of Other Assets

The following table provides the detail of our other assets.

(Dollars in millions)	December 31, 2020		December 31, 2019
Accrued interest receivable	$	1,933	$	1,952
Benefit and insurance-related investments		469		459
Income tax asset, net		454		258
Derivatives at fair value		307		212
Fixed assets, net		116		135
Accounts receivable		118		119
Other		95		199
Total	$	3,492	$	3,334

Commitments, Contingencies and Guarantees

12 Months Ended

Dec. 31, 2020

Commitments And Contingencies Disclosure [Abstract]

Commitments, Contingencies and Guarantees

12. Commitments, Contingencies and Guarantees

Legal Proceedings

We and our subsidiaries and affiliates are subject to various claims, lawsuits and other actions that arise in the normal course of business. We believe that these claims, lawsuits and other actions will not, individually or in the aggregate, have a material adverse effect on our business, financial condition or results of operations, except as otherwise disclosed. Most of these matters are claims including individual and class action lawsuits against our servicing or business processing subsidiaries alleging the violation of state or federal laws in connection with servicing or collection activities on their education loans and other debts.

In the ordinary course of our business, the Company and our subsidiaries and affiliates receive information and document requests and investigative demands from various entities including State Attorneys General, U.S. Attorneys, legislative committees, individual members of Congress and administrative agencies. These requests may be informational, regulatory or enforcement in nature and may relate to our business practices, the industries in which we operate, or companies with whom we conduct business. Generally, our practice has been and continues to be to cooperate with these bodies and to be responsive to any such requests.

The number of these inquiries and the volume of related information demands continue to increase and therefore continue to increase the time, costs and resources we must dedicate to timely respond to these requests and may, depending on their outcome, result in payments of restitution, fines and penalties.

Certain Cases

During the first quarter of 2016, Navient Corporation, certain Navient officers and directors, and the underwriters of certain Navient securities offerings were sued in three putative securities class action lawsuits filed on behalf of certain investors in Navient stock or Navient unsecured debt. These three cases, which were filed in the U.S. District Court for the District of Delaware, were consolidated by the District Court, with Lord Abbett Funds appointed as Lead Plaintiff. The caption of the consolidated case is Lord Abbett Affiliated Fund, Inc., et al. v. Navient Corporation, et al. The plaintiffs filed their amended and consolidated complaint in September 2016. In September 2017, the Court granted the Navient defendants’ motion and dismissed the complaint in its entirety with leave to amend. The plaintiffs filed a second amended complaint with the court in November 2017 and the Navient defendants filed a motion to dismiss the second amended complaint in January 2018. In January 2019, the Court granted-in-part and denied-in-part the Navient defendants’ motion to dismiss. The Navient defendants deny the allegations and intend to vigorously defend against the allegation in this lawsuit. Discovery is on-going. Additionally, two putative class actions have been filed in the U.S. District Court for the District of New Jersey captioned Eli Pope v. Navient Corporation, John F. Remondi, Somsak Chivavibul and Christian Lown, and Melvin Gross v. Navient Corporation, John F. Remondi, Somsak Chivavibul and Christian M. Lown, both of which allege violations of the federal securities laws under Sections 10(b) and 20(a) of the Securities Exchange Act of 1934. After the cases were consolidated by the Court in February 2018 under the caption In Re Navient Corporation Securities Litigation, the plaintiffs filed a consolidated amended complaint in April 2018 and the Company filed a motion to dismiss in June 2018. In December 2019, the Court denied the Company’s motion to dismiss and discovery is on-going. The Company continues to deny the allegations and intends to vigorously defend itself.

In addition, the Company has been named as defendant in a number of putative class action cases alleging violations of various state and federal consumer protection laws including the Telephone Consumer Protection Act (TCPA), the Consumer Financial Protection Act of 2010 (CFPA), the Fair Credit Reporting Act (FCRA), the Fair Debt Collection Practices Act (FDCPA) and various other state consumer protection laws.

At this point in time, the Company is unable to anticipate the timing of a resolution or the impact that these legal proceedings discussed above may have on the Company’s consolidated financial position, liquidity, results of operation or cash flows. As a result, it is not possible at this time to estimate a range of potential exposure, if any, for amounts that may be payable in connection with these matters and reserves have not been established. It is possible that an adverse ruling or rulings may have a material adverse impact on the Company.

12. Commitments, Contingencies and Guarantees (Continued)

In January 2017, the Consumer Financial Protection Bureau (the CFPB) and Attorneys General for the State of Illinois and the State of Washington initiated civil actions naming Navient Corporation and several of its subsidiaries as defendants alleging violations of certain Federal and State consumer protection statutes, including the CFPA, FCRA, FDCPA and various state consumer protection laws. In October 2017, the Attorney General for the Commonwealth of Pennsylvania initiated a civil action against Navient Corporation and Navient Solutions, LLC (Solutions), containing similar alleged violations of the CFPA and the Pennsylvania Unfair Trade Practices and Consumer Protection Law. The Attorneys General for the States of California, Mississippi and, in October 2020, New Jersey have also initiated actions against the Company and certain subsidiaries alleging violations of various state and federal consumer protection laws based upon similar alleged acts or failures to act. We refer to the Illinois, Pennsylvania, Washington, California, Mississippi and New Jersey Attorneys General collectively as the “State Attorneys General.” In addition to these matters, a number of lawsuits have been filed by nongovernmental parties or, in the future, may be filed by additional governmental or nongovernmental parties seeking damages or other remedies related to similar issues raised by the CFPB and the State Attorneys General. As the Company has previously stated, we believe the suits improperly seek to impose penalties on Navient based on new, previously unannounced servicing standards applied retroactively against only one servicer, and that the allegations are false. We therefore have denied these allegations and are vigorously defending against the allegations in each of these cases. At this point in time, it is reasonably possible that a loss contingency exists; however, the Company is unable to anticipate the timing of a resolution or the impact that these legal proceedings may have on the Company’s consolidated financial position, liquidity, results of operation or cash flows. As a result, it is not possible at this time to estimate a range of potential exposure, if any, for amounts that may be payable in connection with these matters and reserves have not been established. It is possible that an adverse ruling or rulings may have a material adverse impact on the Company.

Regulatory Matters

In addition, Navient and its subsidiaries are subject to examination or regulation by various federal regulatory, state licensing or other regulatory agencies as part of its ordinary course of business including the SEC, CFPB, FFIEC and ED. Items or matters similar to or different from those described above may arise during the course of those examinations. We also routinely receive inquiries or requests from various regulatory entities or bodies or government agencies concerning our business or our assets. Generally, the Company endeavors to cooperate with each such inquiry or request. The Company subsequently received separate but similar CIDs or subpoenas from the Attorneys General for the District of Columbia, Kansas, Oregon, Colorado, New Jersey, New York and Indiana. We have and, in the future, may receive additional CIDs or subpoenas and other inquiries from these or other Attorneys General with respect to similar or different matters.

Under the terms of the Separation and Distribution Agreement between the Company and SLM BankCo, Navient agreed to indemnify SLM BankCo for claims, actions, damages, losses or expenses that may arise from the conduct of activities of pre-Spin-Off SLM BankCo occurring prior to the Spin-Off other than those specifically excluded in that agreement. Also, as part of the Separation and Distribution Agreement, SLM BankCo agreed to indemnify Navient for certain claims, actions, damages, losses or expenses subject to the terms, conditions and limitations set forth in that agreement. As a result, subject to the terms, conditions and limitations set forth in that agreement, Navient agreed to indemnify and hold harmless Sallie Mae and its subsidiaries, including Sallie Mae Bank from liabilities arising out of the regulatory matters and CFPB and State Attorneys General lawsuits mentioned above. In addition, we asserted various claims for indemnification against Sallie Mae and Sallie Mae Bank for such specifically excluded items arising out of the CFPB and the State Attorneys General lawsuits if and to the extent any indemnified liabilities exist now or in the future. We expect these various indemnification claims to be resolved at a future date as the cases move toward conclusion. Navient has no reserves related to indemnification matters with SLM BankCo as of December 31, 2020.

12. Commitments, Contingencies and Guarantees (Continued)

OIG Audit

The Office of the Inspector General (the OIG) of ED commenced an audit regarding Special Allowance Payments (SAP) on September 10, 2007. In September 2013, we received the final audit determination of Federal Student Aid (the Final Audit Determination) on the final audit report issued by the OIG in August 2009 related to this audit. The Final Audit Determination concurred with the final audit report issued by the OIG and instructed us to make adjustment to our government billing to reflect the policy determination. In August 2016, we filed our notice of appeal to the Administrative Actions and Appeals Service Group of ED, and a hearing was held in April 2017. In March 2019, the administrative law judge hearing the appeal affirmed the audit’s findings, holding the then-existing Dear Colleague letter relied upon by the Company and other industry participants was inconsistent with the statutory framework creating the SAP rules applicable to loans funded by certain types of debt obligations at issue. We appealed the administrative law judge’s decision to the Secretary of Education given Navient’s adherence to ED-issued guidance and the potential impact on participants in any ED program student loan servicers if such guidance is deemed unreliable and may not be relied upon. In January 2021, the Acting Secretary of Education upheld the decision of the administrative law judge. We continue to believe that our SAP billing practices were proper, considering then-existing ED guidance and lack of applicable regulations and are assessing whether to further appeal this decision. The Company first established a reserve for this matter in 2014 and increased the reserve in 2020 in response to the recent decision by the Acting Secretary. We do not believe, at this time, that an adverse ruling will have a material effect on the Company as a whole.

Contingencies

In the ordinary course of business, we and our subsidiaries are defendants in or parties to pending and threatened legal actions and proceedings including actions brought on behalf of various classes of claimants. These actions and proceedings may be based on alleged violations of consumer protection, securities, employment and other laws. In certain of these actions and proceedings, claims for substantial monetary damage are asserted against us and our subsidiaries. We and our subsidiaries are also subject to potential unasserted claims by third parties.

In the ordinary course of business, we and our subsidiaries are subject to regulatory examinations, information gathering requests, inquiries and investigations. In connection with formal and informal inquiries in these cases, we and our subsidiaries receive requests, subpoenas and orders for documents, testimony and information in connection with various aspects of our regulated activities.

We are required to establish reserves for litigation and regulatory matters where those matters present loss contingencies that are both probable and estimable. When loss contingencies are not both probable and estimable, we do not establish reserves.

In view of the inherent difficulty of predicting the outcome of litigation and regulatory matters, we may not be able to predict what the eventual outcome of the pending matters will be, what the timing or the ultimate resolution of these matters will be, or what the eventual loss, fines or penalties, if any, related to each pending matter may be.

Based on current knowledge, reserves have been established for certain litigation, regulatory matters, and unasserted contract claims where the loss is both probable and estimable. Based on current knowledge, management does not believe that loss contingencies, if any, arising from pending investigations, litigation or regulatory matters will have a material adverse effect on our consolidated financial position, liquidity, results of operations or cash flows, except as otherwise disclosed.

Earnings (Loss) per Common Share - Schedule of Earnings (Loss) per Common Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Numerator:
Net income	$ 412	$ 597	$ 395
Denominator:
Weighted average shares used to compute basic EPS	193	230	260
Effect of dilutive securities:
Dilutive effect of stock options, restricted stock, restricted stock units, performance stock units, and Employee Stock Purchase Plan ("ESPP")	2	3	4
Dilutive potential common shares	2	3	4
Weighted average shares used to compute diluted EPS	195	233	264
Basic earnings per common share	$ 2.14	$ 2.59	$ 1.52
Diluted earnings per common share	$ 2.12	$ 2.56	$ 1.49

Segment Reporting - Segment Result and Reconciliations to GAAP - Core Earnings Adjustments (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting, Revenue Reconciling Item [Line Items]
Net interest income (loss) after provisions for loan losses	$ 1,097	$ 927	$ 870
Total other income (loss)	430	856	702
Goodwill and acquired intangible asset impairment and amortization	22	30	47
Income tax expense (benefit)	120	166	133
Net income	412	597	395
Total Adjustments [Member] \| Adjustments [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Net interest income (loss) after provisions for loan losses	(9)	(31)	(49)
Total other income (loss)	(256)	36	(41)
Goodwill and acquired intangible asset impairment and amortization	22	30	47
Total Core Earnings adjustments to GAAP	(287)	(25)	(137)
Income tax expense (benefit)	(68)	(15)	(13)
Net income	(219)	(10)	(124)
Net Impact of Goodwill and Acquired Intangible Assets [Member] \| Total Adjustments [Member] \| Adjustments [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Goodwill and acquired intangible asset impairment and amortization	22	30	47
Total Core Earnings adjustments to GAAP	(22)	(30)	(47)
Net Impact of Derivative Accounting [Member] \| Total Adjustments [Member] \| Adjustments [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Net interest income (loss) after provisions for loan losses	(9)	(31)	(49)
Total other income (loss)	(256)	36	(41)
Total Core Earnings adjustments to GAAP	$ (265)	$ 5	$ (90)

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Allowance for loans losses	$ 1,377	$ 1,112
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,125,000,000	1,125,000,000
Common stock, shares issued	454,000,000	451,000,000
Tax (benefit) expense for accumulated other comprehensive income	$ 90	$ 30
Common stock held in treasury	267,000,000	236,000,000
FFELP Loans [Member]
Allowance for loans losses	$ 288	$ 64
Private Education Loans [Member]
Allowance for loans losses	$ 1,089	$ 1,048

Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Dividends per common share	$ 0.64	$ 0.64	$ 0.64
Retained Earnings [Member]
Dividends per common share	0.64	0.64	0.64
Total Stockholders' Equity [Member]
Dividends per common share	$ 0.64	$ 0.64	$ 0.64

Organization and Business - Additional Information (Detail) Customer in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) Customer Client	Dec. 31, 2019 USD ($)
Organization And Business [Line Items]
Loans, net	$ 79,363	$ 86,820
FFELP Loans [Member]
Organization And Business [Line Items]
Loans, net	58,284	64,575
Private Education Loans [Member]
Organization And Business [Line Items]
Loans, net	21,079	22,245
Federal Education Loans [Member]
Organization And Business [Line Items]
Loans, net	$ 58,284	64,575
Loans serviced to customers on behalf of the U.S. Department of Education (ED) \| Customer	5.6
Federal Education Loans [Member] \| FFELP Loans [Member]
Organization And Business [Line Items]
Loans, net	$ 58,300
Consumer Lending [Member]
Organization And Business [Line Items]
Loans, net	21,079	$ 22,245
Consumer Lending [Member] \| Private Education Loans [Member]
Organization And Business [Line Items]
Loans, net	21,100
Loans originated	$ 4,600
Business Processing [Member] \| Minimum [Member]
Organization And Business [Line Items]
Number of clients for business processing services \| Client	500

Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2020

ASU 2016-13 [Member]

Summary of Translation Adjustments in Connection with Adopting CECL

(Dollars in millions)	FFELP Loans		Private Education Loans			Total
Allowance as of December 31, 2019 (prior to CECL)	$	64	$	1,048		$	1,112
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses on non-PCD portfolio⁽¹⁾		260		542			802
Current expected credit losses on PCD portfolio⁽²⁾		—		43			43
Reclassification of the expected future recoveries on charged-off loans⁽³⁾		—		(588	)		(588	)
Net increase to allowance for loan losses under CECL		260		(3	)		257
Allowance as of January 1, 2020 after CECL	$	324	$	1,045		$	1,369

⁽¹⁾	Recorded net of tax through retained earnings. Resulted in a $620 million reduction to equity.

⁽²⁾	Recorded as an increase in basis of the loans. No impact to equity.

⁽³⁾	Reclassification of the expected future recoveries on charged-off loans (previously referred to as the receivable for partially charged-off loans) from the Private Education Loan balance to the allowance for loan losses. No impact to equity.

Earnings (Loss) per Common Share (Tables)

12 Months Ended

Dec. 31, 2020

Earnings Per Share [Abstract]

Schedule of Earnings (Loss) per Common Share

	Years Ended December 31,
(In millions, except per share data)	2020		2019		2018
Numerator:
Net income	$	412	$	597	$	395
Denominator:
Weighted average shares used to compute basic EPS		193		230		260
Effect of dilutive securities:
Dilutive effect of stock options, restricted stock, restricted stock units, performance stock units and Employee Stock Purchase Plan (ESPP)⁽¹⁾		2		3		4
Dilutive potential common shares⁽²⁾		2		3		4
Weighted average shares used to compute diluted EPS		195		233		264
Basic earnings per common share	$	2.14	$	2.59	$	1.52
Diluted earnings per common share	$	2.12	$	2.56	$	1.49

⁽¹⁾

⁽²⁾	For the years ended December 31, 2020, 2019 and 2018, stock options covering approximately 2 million, 4 million and 6 million shares, respectively, were outstanding but not included in the computation of diluted earnings per share because they were anti-dilutive.

Stockholders' Equity

12 Months Ended

Dec. 31, 2020

Equity [Abstract]

Stockholders' Equity

9. Stockholders’ Equity

Common Stock

Our shareholders have authorized the issuance of 1.125 billion shares of common stock. The par value of Navient common stock is $0.01 per share. At December 31, 2020, 186 million shares were issued and outstanding and 23 million shares were unissued but encumbered for outstanding stock options, restricted stock units, performance stock units and dividend equivalent units for employee compensation and remaining authority for stock-based compensation plans.

Dividend and Share Repurchase Program

On January 27, 2020, Navient entered into an agreement and repurchased 20.3 million shares of common stock owned by certain existing shareholders at a purchase price of $14.77 per share. The price of the shares repurchased equaled the closing price of Navient stock on January 27, 2020.

The following table summarizes our common share repurchases, issuances and dividends paid.

	Years Ended December 31,
(Dollars and shares in millions, except per share amounts)	2020		2019		2018
Common stock repurchased⁽¹⁾		30.6		34.5		17.4
Common stock repurchased (in dollars)⁽¹⁾	$	400	$	440	$	220
Average purchase price per share⁽¹⁾	$	13.06	$	12.76	$	12.64
Remaining common stock repurchase authority⁽¹⁾	$	600	$	1,000	$	440
Shares repurchased related to employee stock-based compensation plans⁽²⁾		1.2		3.2		3.8
Average purchase price per share⁽²⁾	$	12.86	$	11.62	$	13.71
Common shares issued⁽³⁾		2.7		5.7		5.7
Dividends paid	$	123	$	147	$	166
Dividends per share	$	.64	$	.64	$	.64

⁽¹⁾

Common shares purchased under our share repurchase program. Our board of directors authorized a $500 million share repurchase program in September 2018 which was fully utilized in 2019 and in October 2019, an additional $1 billion multi-year program was approved.

⁽²⁾

Comprises shares withheld from stock option exercises and vesting of restricted stock for employees’ tax withholding obligations and shares tendered by employees to satisfy option exercise costs.

⁽³⁾

Common shares issued under our various compensation and benefit plans.

The closing price of our common stock on December 31, 2020 was $9.82.

Education Loans (Tables)

12 Months Ended

Dec. 31, 2020

Receivables [Abstract]

Education Loan Portfolio by Program

The estimated weighted average life of education loans in our portfolio was approximately 6 years at December 31, 2020 and 2019. The following table reflects the distribution of our education loan portfolio by program.

	December 31, 2020					Year Ended December 31, 2020
(Dollars in millions)	Ending Balance		% of Balance			Average Balance		Average Effective Interest Rate
FFELP Stafford Loans, net	$	19,607		25	%	$	20,844		2.80	%
FFELP Consolidation Loans, net		38,677		49			40,678		3.08
Private Education Loans, net		21,079		26			22,720		6.36
Total education loans, net	$	79,363		100	%	$	84,242		3.90	%

	December 31, 2019					Year Ended December 31, 2019
(Dollars in millions)	Ending Balance		% of Balance			Average Balance		Average Effective Interest Rate
FFELP Stafford Loans, net	$	21,723		25	%	$	23,198		4.24	%
FFELP Consolidation Loans, net		42,852		49			45,073		4.13
Private Education Loans, net		22,245		26			22,512		7.69
Total education loans, net	$	86,820		100	%	$	90,783		5.04	%

Other Assets

12 Months Ended

Dec. 31, 2020

Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]

Other Assets

8. Other Assets

The following table provides the detail of our other assets.

(Dollars in millions)	December 31, 2020		December 31, 2019
Accrued interest receivable	$	1,933	$	1,952
Benefit and insurance-related investments		469		459
Income tax asset, net		454		258
Derivatives at fair value		307		212
Fixed assets, net		116		135
Accounts receivable		118		119
Other		95		199
Total	$	3,492	$	3,334

Revenue from Contracts with Customers Accounted for in Accordance with ASC 606

12 Months Ended

Dec. 31, 2020

Revenue From Contract With Customer [Abstract]

Revenue from Contracts with Customers Accounted for in Accordance with ASC 606

14. Revenue from Contracts with Customers Accounted for in Accordance with ASC 606

The following tables illustrate the disaggregation of revenue from contracts accounted for under ASC 606 with customers according to service type and client type by reportable operating segment.

Revenue by Service Type

	Years Ended December 31,
	2020						2019
(Dollars in millions)	Federal Education Loans		Business Processing		Total Revenue		Federal Education Loans		Business Processing		Total Revenue
Federal Education Loan asset recovery services	$	84	$	—	$	84	$	133	$	—	$	133
Government services		—		191		191		—		154		154
Healthcare services		—		113		113		—		104		104
Total	$	84	$	304	$	388	$	133	$	258	$	391

Revenue by Client Type

	Years Ended December 31,
	2020						2019
(Dollars in millions)	Federal Education Loans		Business Processing		Total Revenue		Federal Education Loans		Business Processing		Total Revenue
Federal government	$	44	$	18	$	62	$	74	$	17	$	91
Guarantor agencies		38		—		38		52		—		52
Other institutions		2		—		2		7		—		7
State and local government		—		122		122		—		83		83
Tolling authorities		—		51		51		—		54		54
Hospitals and other healthcare providers		—		113		113		—		104		104
Total	$	84	$	304	$	388	$	133	$	258	$	391

As of December 31, 2020 and 2019, there was $90 million and $67 million, respectively, of net accounts receivable related to these contracts. Navient had no material contract assets or contract liabilities.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

+ Details

Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest income:
Cash and investments	$ 16	$ 93	$ 97
Total interest income	3,298	4,673	4,908
Total interest expense	2,046	3,488	3,668
Net interest income	1,252	1,185	1,240
Less: provisions for loan losses	155	258	370
Net interest income after provisions for loan losses	1,097	927	870
Other income (loss):
Servicing revenue	214	240	274
Asset recovery and business processing revenue	458	488	430
Other income	20	45	17
Gains on sales of loans		16
Gains (losses) on debt repurchases	(6)	45	19
Gains (losses) on derivative and hedging activities, net	(256)	22	(38)
Total other income	430	856	702
Expenses:
Salaries and benefits	497	488	507
Other operating expenses	467	496	477
Total operating expenses	964	984	984
Goodwill and acquired intangible asset impairment and amortization expense	22	30	47
Restructuring/other reorganization expenses	9	6	13
Total expenses	995	1,020	1,044
Income before income tax expense	532	763	528
Income tax expense	120	166	133
Net income	$ 412	$ 597	$ 395
Basic earnings per common share	$ 2.14	$ 2.59	$ 1.52
Average common shares outstanding	193	230	260
Diluted earnings per common share	$ 2.12	$ 2.56	$ 1.49
Average common and common equivalent shares outstanding	195	233	264
Dividends per common share	$ 0.64	$ 0.64	$ 0.64
FFELP Loans [Member]
Interest income:
Total interest income	$ 1,837	$ 2,847	$ 3,027
Less: provisions for loan losses	13	30	70
Private Education Loans [Member]
Interest income:
Total interest income	1,445	1,731	1,778
Less: provisions for loan losses	$ 142	226	299
Other Loans [Member]
Interest income:
Total interest income		$ 2	$ 6

Borrowings - Company's Borrowings (Parenthetical) (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Short-term Debt	$ 6,613.0	$ 8,483.0
Long-term debt	77,332.0	81,715.0
Total Before Hedge Accounting Adjustments [Member]
Debt Instrument [Line Items]
Short-term Debt	6,609.0	8,479.0
Long-term debt	76,781.0	81,756.0
Total Before Hedge Accounting Adjustments [Member] \| FFELP Loan Asset-backed Securitization Repurchase Facilities [Member]
Debt Instrument [Line Items]
Short-term Debt	0.0	72.0
Long-term debt	157.0	231.0
Total Before Hedge Accounting Adjustments [Member] \| Non-U.S. Doller Denominated Debt [Member]
Debt Instrument [Line Items]
Long-term debt	3,600.0	4,000.0
Total Before Hedge Accounting Adjustments [Member] \| Private Education Loan Asset-backed Securitization Repurchase Facilities [Member]
Debt Instrument [Line Items]
Short-term Debt	960.0	2,100.0
Long-term debt	260.0	194.0
Total Before Hedge Accounting Adjustments [Member] \| Long-Term Floating Rate Debt [Member]
Debt Instrument [Line Items]
Long-term debt	60.0	67.7
Total Before Hedge Accounting Adjustments [Member] \| Long-Term Fixed Rate Debt [Member]
Debt Instrument [Line Items]
Long-term debt	16.8	14.0
Total Before Hedge Accounting Adjustments [Member] \| Short Term Senior Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt principal amount	678.0	1,100.0
Total Before Hedge Accounting Adjustments [Member] \| Long Term Senior Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt principal amount	$ 7,800.0	$ 8,500.0

Stockholders' Equity - Common Share Repurchases, Issuances and Dividends Paid (Detail) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	Jan. 27, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Equity, Class of Treasury Stock [Line Items]
Average purchase price per share		$ 13.06	$ 12.76	$ 12.64
Remaining common stock repurchase authority		$ 600	$ 1,000	$ 440
Shares repurchased related to employee stock-based compensation plans		1,200,000	3,200,000	3,800,000
Average purchase price per share		$ 12.86	$ 11.62	$ 13.71
Common shares issued		2,700,000	5,700,000	5,700,000
Dividends paid		$ 123	$ 147	$ 166
Dividends per common share		$ 0.64	$ 0.64	$ 0.64
Common Stock Shares Outstanding [Member]
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased, shares	20,300,000	30,600,000	34,500,000	17,400,000
Common stock repurchased, value		$ 400	$ 440	$ 220
Average purchase price per share	$ 14.77
Shares repurchased related to employee stock-based compensation plans		1,189,745	3,226,301	3,829,629
Common shares issued		2,684,096	5,717,053	5,659,681

Derivative Financial Instruments - Mark-to-Market Impact of Derivatives on Statements of Income (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Mark-to-market gains (losses) recognized	$ (256)	$ 22	$ (38)
Interest Expense and Derivative Instruments Hedging Activities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Mark-to-market gains (losses) recognized	(273)	43	(38)
Designated as Hedging Instrument [Member] \| Fair Value [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Mark-to-market gains (losses) recognized	(17)	21	(76)
Designated as Hedging Instrument [Member] \| Fair Value [Member] \| Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in net income on derivatives	301	281	(137)
Gains (losses) recognized in net income on hedged items	(327)	(299)	162
Net fair value hedge ineffectiveness gains (losses)	(26)	(18)	25
Designated as Hedging Instrument [Member] \| Fair Value [Member] \| Cross-Currency Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in net income on derivatives	281	57	(311)
Gains (losses) recognized in net income on hedged items	(272)	(18)	210
Net fair value hedge ineffectiveness gains (losses)	9	39	(101)
Trading [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Mark-to-market gains (losses) recognized	(256)	22	38
Trading [Member] \| Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Mark-to-market gains (losses) recognized	(47)	44	22
Trading [Member] \| Cross-Currency Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Mark-to-market gains (losses) recognized		(2)	(3)
Trading [Member] \| Floor Income Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Mark-to-market gains (losses) recognized	$ (209)	(22)	15
Trading [Member] \| Other [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Mark-to-market gains (losses) recognized		$ 2	$ 4

Fair Value Measurements

12 Months Ended

Dec. 31, 2020

Fair Value Disclosures [Abstract]

Fair Value Measurements

11. Fair Value Measurements

We use estimates of fair value in applying various accounting standards in our financial statements. We categorize our fair value estimates based on a hierarchical framework associated with three levels of price transparency utilized in measuring financial instruments at fair value. The fair value of the items discussed below are separately disclosed in this footnote.

During 2020, there were no significant transfers of financial instruments between levels, or changes in our methodology used to value our financial instruments. The fair values take into account the impact COVID-19 had on the valuations as of December 31, 2020, generally in the form of higher credit spreads used to determine the respective fair values of our education loans and borrowings.

Education Loans

Our FFELP Loans and Private Education Loans are accounted for at cost or at the lower of cost or market if the loan is held-for-sale. Fair values are determined by modeling loan cash flows using stated terms of the assets using mostly internally developed assumptions that are validated against market transactions when available.

FFELP Loans

The significant assumptions used to determine fair value of our FFELP Loans are prepayment speeds, default rates, cost of funds, discount rate, capital levels and expected Repayment Borrower Benefits to be earned. In addition, the Floor Income component of our FFELP Loan portfolio is valued with option models using both observable market inputs and internally developed inputs. A number of significant inputs into the models are internally derived and not observable in active markets. While the resulting fair value can be validated against market transactions where we are a participant, these markets are not considered active. As such, these are level 3 valuations.

Private Education Loans

The significant assumptions used to determine fair value of our Private Education Loans are prepayment speeds, default rates, recovery rates, cost of funds, discount rate and capital levels. A number of significant inputs into the models are internally derived and not observable in active markets. While the resulting fair value can be validated against market transactions where we are a participant, these markets are not considered active. As such, these are level 3 valuations.

Cash and Investments (Including “Restricted Cash and Investments”)

Cash and cash equivalents are carried at cost. Carrying value approximates fair value. The fair value of investments in commercial paper, ABCP, or demand deposits that have a remaining term of less than 90 days when purchased are estimated to equal their cost and, when needed, adjustments for liquidity and credit spreads are made depending on market conditions and counterparty credit risks. No additional adjustments were deemed necessary. These investments are level 2 valuations.

Borrowings

Borrowings are accounted for at cost in the financial statements except when denominated in a foreign currency or when designated as the hedged item in a fair value hedge relationship. When the hedged risk is the benchmark interest rate (which for us is LIBOR) and not full fair value, the cost basis is adjusted for changes in value due to benchmark interest rates only. Foreign currency-denominated borrowings are re-measured at current spot rates in the financial statements. Fair value was determined through standard bond pricing models and option models (when applicable) using the stated terms of the borrowings, observable yield curves, foreign currency exchange rates, volatilities from active markets or from quotes from broker-dealers. Fair value adjustments for unsecured corporate debt are made based on indicative quotes from observable trades and spreads on credit default swaps specific to the Company. Fair value adjustments for secured borrowings are based on indicative quotes from broker-dealers. These adjustments for both secured and unsecured borrowings are material to the overall valuation of these items and, currently, are based on inputs from inactive markets. As such, these are level 3 valuations.

11. Fair Value Measurements (Continued)

Derivative Financial Instruments

All derivatives are accounted for at fair value in the financial statements. The fair value of a majority of derivative financial instruments was determined by standard derivative pricing and option models using the stated terms of the contracts and observable market inputs and are therefore classified as level 2 fair values. In some cases, we utilized internally developed inputs that are not observable in the market, and as such, classified these instruments as level 3 fair values. Complex structured derivatives or derivatives that trade in less liquid markets require significant estimates and judgment in determining fair value that cannot be corroborated with market transactions.

When determining the fair value of derivatives, we take into account counterparty credit risk for positions where there is exposure to the counterparty on a net basis by assessing exposure net of collateral held. See “Note 7 – Derivative Financial Instruments” for further discussion on methodology. The net credit risk adjustment (adjustments for our exposure to counterparties net of adjustments for the counterparties’ exposure to us) decreased the valuations at December 31, 2020 by $8 million.

Inputs specific to each class of derivatives disclosed in the table below are as follows:

•

Interest rate swaps — Fair value is determined using standard derivative cash flow models. Derivatives that swap fixed interest payments for LIBOR interest payments (or vice versa) and derivatives swapping quarterly reset LIBOR for daily reset LIBOR or one-month LIBOR were valued using the LIBOR swap yield curve which is an observable input from an active market. These derivatives are level 2 fair value estimates in the hierarchy. Other derivatives swapping LIBOR interest payments for another variable interest payment (primarily Prime) are valued using the LIBOR swap yield curve and observable market spreads for the specified index. The markets for these swaps are generally illiquid as indicated by a wide bid/ask spread. The adjustment made for liquidity decreased the valuations by $5 million at December 31, 2020. These derivatives are level 3 fair value estimates.

•

Cross-currency interest rate swaps — Fair value is determined using standard derivative cash flow models. Derivatives hedging foreign-denominated bonds are valued using the LIBOR swap yield curve (for both USD and the foreign-denominated currency), cross-currency basis spreads and forward foreign currency exchange rates. These inputs are observable inputs from active markets. Therefore, the resulting valuation is a level 2 fair value estimate. Amortizing notional derivatives (derivatives whose notional amounts change based on changes in the balance of, or pool of, assets or debt) hedging trust debt use internally derived assumptions for the trust assets’ prepayment speeds and default rates to model the notional amortization. Management makes assumptions concerning the extension features of derivatives hedging rate-reset notes denominated in a foreign currency. These inputs are not market observable; therefore, these derivatives are level 3 fair value estimates.

•

Floor Income Contracts — Derivatives are valued using an option pricing model. Inputs to the model include the LIBOR swap yield curve and LIBOR interest rate volatilities. The inputs are observable inputs in active markets and these derivatives are level 2 fair value estimates.

The carrying value of borrowings designated as the hedged item in a fair value hedge is adjusted for changes in fair value due to benchmark interest rates and foreign-currency exchange rates. These valuations are determined through standard bond pricing models and option models (when applicable) using the stated terms of the borrowings, and observable yield curves, foreign currency exchange rates and volatilities.

11. Fair Value Measurements (Continued)

	Fair Value Measurements on a Recurring Basis
	December 31, 2020											December 31, 2019
(Dollars in millions)	Level 1		Level 2			Level 3			Total			Level 1		Level 2			Level 3			Total
Assets
Derivative instruments:⁽¹⁾
Interest rate swaps		—		323			6			329			—		227			3			230
Cross-currency interest rate swaps		—		—			28			28			—		—			—			—
Total derivative assets⁽²⁾		—		323			34			357			—		227			3			230
Total	$	—	$	323		$	34		$	357		$	—	$	227		$	3		$	230
Liabilities⁽³⁾
Derivative instruments⁽¹⁾
Interest rate swaps	$	—	$	—		$	(14	)	$	(14	)	$	—	$	—		$	(20	)	$	(20	)
Floor Income Contracts		—		(197	)		—			(197	)		—		(68	)		—			(68	)
Cross-currency interest rate swaps		—		—			(322	)		(322	)		—		—			(575	)		(575	)
Other		—		—			—			—			—		—			(1	)		(1	)
Total derivative liabilities⁽²⁾		—		(197	)		(336	)		(533	)		—		(68	)		(596	)		(664	)
Total	$	—	$	(197	)	$	(336	)	$	(533	)	$	—	$	(68	)	$	(596	)	$	(664	)

⁽¹⁾	Fair value of derivative instruments excludes accrued interest and the value of collateral.

⁽²⁾	See “Note 7 — Derivative Financial Instruments” for a reconciliation of gross positions without the impact of master netting agreements to the balance sheet classification.

⁽³⁾	Borrowings which are the hedged item in a fair value hedge relationship and which are adjusted for changes in value due to benchmark interest rates only are not carried at full fair value and not reflected in this table.

11. Fair Value Measurements (Continued)

The following tables summarize the change in balance sheet carrying value associated with level 3 financial instruments carried at fair value on a recurring basis.

	Year Ended December 31, 2020
	Derivative Instruments
(Dollars in millions)	Interest Rate Swaps			Cross Currency Interest Rate Swaps			Other			Total Derivative Instruments
Balance, beginning of period	$	(17	)	$	(575	)	$	(1	)	$	(593	)
Total gains/(losses):
Included in earnings⁽¹⁾		8			231			—			239
Included in other comprehensive income		—			—			—			—
Settlements		1			50			1			52
Transfers in and/or out of level 3		—			—			—			—
Balance, end of period	$	(8	)	$	(294	)	$	—		$	(302	)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date⁽²⁾	$	5		$	273		$	1		$	279

	Year Ended December 31, 2019
	Derivative Instruments
(Dollars in millions)	Interest Rate Swaps			Cross Currency Interest Rate Swaps			Other			Total Derivative Instruments
Balance, beginning of period	$	(27	)	$	(633	)	$	(4	)	$	(664	)
Total gains/(losses):
Included in earnings⁽¹⁾		8			(60	)		2			(50	)
Included in other comprehensive income		—			—			—			—
Settlements		2			118			1			121
Transfers in and/or out of level 3		—			—			—			—
Balance, end of period	$	(17	)	$	(575	)	$	(1	)	$	(593	)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date⁽²⁾	$	9		$	58		$	3		$	70

	Year Ended December 31, 2018
	Derivative Instruments
(Dollars in millions)	Interest Rate Swaps			Cross Currency Interest Rate Swaps			Other			Total Derivative Instruments
Balance, beginning of period	$	(41	)	$	(322	)	$	(18	)	$	(381	)
Total gains/(losses):
Included in earnings⁽¹⁾		11			(433	)		8			(414	)
Included in other comprehensive income		—			—			—			—
Settlements		3			122			6			131
Transfers in and/or out of level 3		—			—			—			—
Balance, end of period	$	(27	)	$	(633	)	$	(4	)	$	(664	)
Change in mark-to-market gains/(losses) relating to instruments still held at the reporting date⁽²⁾	$	13		$	(284	)	$	14		$	(257	)

⁽¹⁾

“Included in earnings” is comprised of the following amounts recorded in the specified line item in the consolidated statements of income:

	Years Ended December 31,
(Dollars in millions)	2020		2019			2018
Gains (losses) on derivative and hedging activities, net	$	8	$	10		$	(292	)
Interest expense		231		(60	)		(122	)
Total	$	239	$	(50	)	$	(414	)

⁽²⁾

Recorded in “gains (losses) on derivative and hedging activities, net” in the consolidated statements of income.

11. Fair Value Measurements (Continued)

The following table presents the significant inputs that are unobservable or from inactive markets used in the recurring valuations of the level 3 financial instruments detailed above.

(Dollars in millions)	Fair Value at December 31, 2020			Valuation Technique	Input	Range and Weighted Average
Derivatives
Prime/LIBOR basis swaps	$	(8	)	Discounted cash flow	Constant Prepayment Rate	9%
					Bid/ask adjustment to discount rate	.08%
Cross-currency interest rate swaps		(294	)	Discounted cash flow	Constant Prepayment Rate	5%
Other		—
Total	$	(302	)

The significant inputs that are unobservable or from inactive markets related to our level 3 derivatives detailed in the table above would be expected to have the following impacts to the valuations:

•

Prime/LIBOR basis swaps — These swaps do not actively trade in the markets as indicated by a wide bid/ask spread. A wider bid/ask spread will result in a decrease in the overall valuation. In addition, the unobservable inputs include Constant Prepayment Rates of the underlying securitization trust the swap references. A decrease in this input will result in a longer weighted average life of the swap which will increase the value for swaps in a gain position and decrease the value for swaps in a loss position, everything else equal. The opposite is true for an increase in the input.

•

Cross-currency interest rate swaps — The unobservable inputs used in these valuations are Constant Prepayment Rates of the underlying securitization trust the swap references. A decrease in this input will result in a longer weighted average life of the swap. All else equal in a typical currency market, this will result in a decrease to the valuation due to the delay in the cash flows of the currency exchanges as well as diminished liquidity in the forward exchange markets as you increase the term. The opposite is true for an increase in the input.

The following table summarizes the fair values of our financial assets and liabilities, including derivative financial instruments.

	December 31, 2020									December 31, 2019
(Dollars in millions)	Fair Value			Carrying Value			Difference			Fair Value			Carrying Value			Difference
Earning assets
FFELP Loans	$	59,117		$	58,284		$	833		$	64,478		$	64,575		$	(97	)
Private Education Loans		22,462			21,079			1,383			22,984			22,245			739
Cash and investments		3,822			3,822			—			3,992			3,992			—
Total earning assets		85,401			83,185			2,216			91,454			90,812			642
Interest-bearing liabilities
Short-term borrowings		6,626			6,613			(13	)		8,498			8,483			(15	)
Long-term borrowings		76,719			77,332			613			81,317			81,715			398
Total interest-bearing liabilities		83,345			83,945			600			89,815			90,198			383
Derivative financial instruments
Floor Income Contracts		(197	)		(197	)		—			(68	)		(68	)		—
Interest rate swaps		315			315			—			210			210			—
Cross-currency interest rate swaps		(294	)		(294	)		—			(575	)		(575	)		—
Other		—			—			—			(1	)		(1	)		—
Excess of net asset fair value over carrying value⁽¹⁾							$	2,816								$	1,025

⁽¹⁾

Borrowings - Expected Maturities of Long-term Borrowings (Parenthetical) (Detail) $ in Billions	Dec. 31, 2020 USD ($)
Debt Disclosure [Abstract]
On-balance sheet securitization trust debt included in projected principal paydowns in 2021	$ 6.8
Aggregate principal amount of debt maturing in 2021	6.8
Aggregate principal amount of debt maturing in 2022	9.0
Aggregate principal amount of debt maturing in 2023	7.6
Aggregate principal amount of debt maturing in 2024	7.2
Aggregate principal amount of debt maturing in 2025	6.1
Aggregate principal amount of debt maturing in 2026-2043	$ 40.7

Business Combinations, Goodwill and Acquired Intangible (Tables)

12 Months Ended

Dec. 31, 2020

Business Combinations [Abstract]

Summary of Goodwill for Each Reporting Units and Reportable Segments

The following table summarizes our goodwill for our reporting units and reportable segments.

(Dollars in millions)	As of Dec. 31, 2020 and Dec. 31, 2019
Federal Education Loans reportable segment:
FFELP Loans	$	227
Federal Education Loan Servicing		13
Total		240
Consumer Lending reportable segment:
Private Education Loans		106
Private Education Refinance Loans		77
Total		183
Business Processing reportable segment:
Government Services		136
Healthcare Services		106
Total		242
Total goodwill	$	665

Acquired Intangible Assets

Acquired intangible assets include the following:

	As of December 31, 2020							As of December 31, 2019
(Dollars in millions)	Cost Basis⁽¹⁾		Accumulated Impairment and Amortization⁽¹⁾⁽²⁾			Net		Cost Basis⁽¹⁾		Accumulated Impairment and Amortization⁽¹⁾⁽²⁾			Net
Customer, services and lending relationships	$	262	$	(230	)	$	32	$	262	$	(220	)	$	42
Software and technology		114		(101	)		13		114		(96	)		18
Trade names and trademarks		52		(27	)		25		52		(20	)		32
Total acquired intangible assets	$	428	$	(358	)	$	70	$	428	$	(336	)	$	92

⁽¹⁾

⁽²⁾

Organization and Business

12 Months Ended

Dec. 31, 2020

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Organization and Business

1. Organization and Business

Navient’s Business

Navient is a leading provider of education loan management and business processing solutions for education, healthcare, and government clients at the federal, state, and local levels. We help our clients and millions of Americans achieve success through technology-enabled financing, services and support.

With a focus on data-driven insights, service, compliance and innovative support, Navient’s business consists of:

•

Federal Education Loans

We own a portfolio of $58.3 billion of federally guaranteed Federal Family Education Loan Program (FFELP) Loans. We service and provide asset recovery services on this portfolio and for third parties, deploying data-driven approaches to support the success of our customers.

We service federal education loans for approximately 5.6 million customers on behalf of the U.S. Department of Education (ED). Our flexible and scalable infrastructure manages large volumes of complex transactions with continued customer experience and efficiency improvements.

•

Consumer Lending

We own, service and originate Private Education Loans that enable students to pursue higher education and economic opportunities. Our $21.1 billion private loan portfolio demonstrates high customer success rates. Our loan origination business assists borrowers in refinancing their education loan debt and supports students and families in financing their higher education. In 2020, we originated $4.6 billion in Private Education Loans.

•

Business Processing

We provide business processing solutions to a variety of public sector and health care organizations. We support over 500 clients – and their millions of clients, patients, and citizens – through a suite of solutions that leverages our scale, technology and customer experience expertise. Our data driven solutions enable our clients to focus on their missions and optimize their cash flow, and they enable individuals to successfully navigate complex programs, transactions, and decisions.

Education Loans

12 Months Ended

Dec. 31, 2020

Receivables [Abstract]

Education Loans

3. Education Loans

Education loans consist of FFELP and Private Education Loans.

There are two principal categories of FFELP Loans: Stafford and FFELP Consolidation Loans. Generally, Stafford loans have repayment periods of between 5 and 10 years. FFELP Consolidation Loans have repayment periods of 12 to 30 years. FFELP Loans do not require repayment, or have modified repayment plans, while the customer is in-school and during the grace period immediately upon leaving school. The customer may also be granted a deferment or forbearance for a period of time based on need, during which time the customer is not considered to be in repayment. Interest continues to accrue on loans in the in-school, deferment and forbearance period. FFELP Loans obligate the customer to pay interest at a stated fixed rate or a variable rate reset annually (subject to a cap) on July 1 of each year depending on when the loan was originated and the loan type. FFELP Loans disbursed before April 1, 2006 earn interest at the greater of the borrower’s rate or a floating rate based on the Special Allowance Payment (SAP) formula, with the interest earned on the floating rate that exceeds the interest earned from the customer being paid directly by ED. For loans disbursed after April 1, 2006, FFELP Loans effectively only earn at the SAP rate, as the excess interest earned when the borrower rate exceeds the SAP rate (Floor Income) is required to be rebated to ED.

FFELP Loans are insured as to their principal and accrued interest in the event of default subject to a Risk Sharing level based on the date of loan disbursement. These insurance obligations are supported by contractual rights against the United States. For loans disbursed after October 1, 1993 and before July 1, 2006, we receive 98% reimbursement on all qualifying default claims. For loans disbursed on or after July 1, 2006, we receive 97% reimbursement.

3. Education Loans (Continued)

Private Education Loans bear the full credit risk of the customer. Private Education Refinance Loans generally have a fixed interest rate with the non-refinance Private Education Loans generally at a variable rate indexed to LIBOR or Prime indices. The majority of non-refinance loans in our portfolio are cosigned. Similar to FFELP loans, Private Education Loans are generally non-dischargeable in bankruptcy. Most loans have repayment terms of 10 to 15 years or more, and for loans made prior to 2009, payments are typically deferred until after graduation. However, since 2009 we began to encourage interest-only or fixed payment options while the customer is enrolled in school.

	December 31, 2020					Year Ended December 31, 2020
(Dollars in millions)	Ending Balance		% of Balance			Average Balance		Average Effective Interest Rate
FFELP Stafford Loans, net	$	19,607		25	%	$	20,844		2.80	%
FFELP Consolidation Loans, net		38,677		49			40,678		3.08
Private Education Loans, net		21,079		26			22,720		6.36
Total education loans, net	$	79,363		100	%	$	84,242		3.90	%

	December 31, 2019					Year Ended December 31, 2019
(Dollars in millions)	Ending Balance		% of Balance			Average Balance		Average Effective Interest Rate
FFELP Stafford Loans, net	$	21,723		25	%	$	23,198		4.24	%
FFELP Consolidation Loans, net		42,852		49			45,073		4.13
Private Education Loans, net		22,245		26			22,512		7.69
Total education loans, net	$	86,820		100	%	$	90,783		5.04	%

As of December 31, 2020 and 2019, 85% and 87%, respectively, of our education loan portfolio was in repayment.

Borrowings - Expected Maturities of Long-term Borrowings (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
2021	$ 6,800
2022	9,000
2023	7,600
2024	7,200
2025	6,100
2026-2043	40,700
Total	77,332	$ 81,715
Fixed Maturities [Member]
Debt Instrument [Line Items]
2021	6,792
2022	8,896
2023	7,541
2024	7,105
2025	6,072
2026-2043	40,375
Long term debt maturities total	76,781
Hedge accounting adjustments	551
Total	77,332
Fixed Maturities [Member] \| Senior Unsecured Debt [Member]
Debt Instrument [Line Items]
2022	1,746
2023	1,506
2024	1,349
2025	550
2026-2043	2,563
Long term debt maturities total	7,714
Hedge accounting adjustments	718
Total	8,432
Fixed Maturities [Member] \| Secured Borrowings [Member]
Debt Instrument [Line Items]
2021	6,792
2022	7,150
2023	6,035
2024	5,756
2025	5,522
2026-2043	37,812
Long term debt maturities total	69,067
Hedge accounting adjustments	(167)
Total	$ 68,900

Income Taxes - Summary of Changes in Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Unrecognized tax benefits at beginning of year	$ 53.6	$ 65.7	$ 57.4
Increases resulting from tax positions taken during a prior period	7.6	4.0	8.0
Decreases resulting from tax positions taken during a prior period		(3.8)	(0.3)
Increases resulting from tax positions taken during the current period	3.5	1.9	3.8
Decreases related to settlements with taxing authorities	(0.2)	(11.1)	(1.4)
Reductions related to the lapse of statute of limitations	(6.6)	(3.1)	(1.8)
Unrecognized tax benefits at end of year	$ 57.9	$ 53.6	$ 65.7

Allowance for Loan Losses - Allowance for Credit Losses and Recorded Investments in Loans (Parenthetical) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts Notes And Loans Receivable [Line Items]
Net adjustment resulting from the change in the charge-off rate	$ (23,000,000)	$ (21,000,000)	$ (32,000,000)
End of period expected recoveries	479,000,000
Change in balance during period	(109,000,000)
FFELP Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Allowance for loans acquired		0	0
Loans receivable, discount		33,000,000	37,000,000
Private Education Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Net adjustment resulting from the change in the charge-off rate	(23,000,000)	(21,000,000)	(32,000,000)
Beginning of period expected recoveries	588,000,000
Expected future recoveries of current period defaults	32,000,000
Recoveries	(107,000,000)
Charge-offs	(34,000,000)
End of period expected recoveries	479,000,000	588,000,000
Change in balance during period	(109,000,000)
Allowance for loans acquired		0	0
Loans receivable, discount		268,000,000	326,000,000
Private Education Loans [Member] \| Loans Receivable For Partially Charged Off Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Net adjustment resulting from the change in the charge-off rate	$ 23,000,000	$ 21,000,000	$ 32,000,000
Private Education Loans [Member] \| Minimum [Member]
Accounts Notes And Loans Receivable [Line Items]
Portion of loan amount charged off at default	81.00%	80.50%	79.00%
Private Education Loans [Member] \| Maximum [Member]
Accounts Notes And Loans Receivable [Line Items]
Portion of loan amount charged off at default	81.40%	81.00%	80.50%

Borrowings (Tables)

12 Months Ended

Dec. 31, 2020

Debt Disclosure [Abstract]

Company's Borrowings

The following table summarizes our borrowings.

	December 31, 2020												December 31, 2019
(Dollars in millions)	Short Term		Weighted Average Interest Rate⁽⁷⁾			Long Term		Weighted Average Interest Rate⁽⁷⁾			Total		Short Term		Weighted Average Interest Rate⁽⁷⁾			Long Term			Weighted Average Interest Rate⁽⁷⁾			Total
Unsecured borrowings:
Senior unsecured debt⁽¹⁾	$	677		6.61	%	$	7,714		6.19	%	$	8,391	$	1,052		6.45	%	$	8,461			6.30	%	$	9,513
Total unsecured borrowings		677		6.61			7,714		6.19			8,391		1,052		6.45			8,461			6.30			9,513
Secured borrowings:
FFELP Loan securitizations⁽²⁾⁽³⁾		—		—			54,697		.89			54,697		72		3.16			59,735			2.45			59,807
Private Education Loan securitizations⁽⁴⁾		960		2.68			13,891		2.04			14,851		2,120		4.14			11,430			3.12			13,550
FFELP Loan ABCP facilities		2,053		1.05			479		1.13			2,532		2,783		2.46			617			2.66			3,400
Private Education Loan ABCP facilities		2,582		1.46			—		—			2,582		2,114		2.76			1,513			3.31			3,627
Other⁽⁵⁾		337		.09			—		—			337		338		1.55			—			—			338
Total secured borrowings		5,932		1.44			69,067		1.12			74,999		7,427		2.99			73,295			2.58			80,722
Total before hedge accounting adjustments⁽⁶⁾		6,609		1.97			76,781		1.63			83,390		8,479		3.42			81,756			2.96			90,235
Hedge accounting adjustments		4		—			551		(.01	)		555		4		—			(41	)		—			(37	)
Total	$	6,613		1.97	%	$	77,332		1.62	%	$	83,945	$	8,483		3.42	%	$	81,715			2.96	%	$	90,198

⁽¹⁾	Includes principal amount of $678 million and $1.1 billion of short-term debt as of December 31, 2020 and 2019, respectively. Includes principal amount of $7.8 billion and $8.5 billion of long-term debt as of December 31, 2020 and 2019, respectively.

⁽²⁾

⁽³⁾	Includes $3.6 billion and $4.0 billion of non-U.S. dollar-denominated debt as of December 31, 2020 and 2019, respectively, which has been hedged with swaps converting to U.S. dollars.

⁽⁴⁾

⁽⁵⁾	“Other” primarily includes the obligation to return cash collateral held related to derivative exposure.

⁽⁶⁾	Includes $60.0 billion and $67.7 billion of long-term floating rate debt as of December 31, 2020 and 2019, respectively, and $16.8 billion and $14.0 billion of long-term fixed rate debt as of December 31, 2020 and 2019, respectively.

⁽⁷⁾	Weighted average interest rate is as of end of period.

Expected Maturities of Long-term Borrowings

As of December 31, 2020, the expected maturities of our long-term borrowings are shown in the following table.

	Expected Maturity
(Dollars in millions)	Senior Unsecured Debt		Secured Borrowings⁽¹⁾			Total⁽²⁾
Year of Maturity
2021	$	—	$	6,792		$	6,792
2022		1,746		7,150			8,896
2023		1,506		6,035			7,541
2024		1,349		5,756			7,105
2025		550		5,522			6,072
2026-2043		2,563		37,812			40,375
		7,714		69,067			76,781
Hedge accounting adjustments		718		(167	)		551
Total	$	8,432	$	68,900		$	77,332

⁽¹⁾

⁽²⁾

Financing VIEs

We consolidated the following financing VIEs as of December 31, 2020 and 2019, as we are the primary beneficiary. As a result, these VIEs are accounted for as secured borrowings.

	December 31, 2020
	Debt Outstanding								Carrying Amount of Assets Securing Debt Outstanding
(Dollars in millions)	Short Term		Long Term			Total			Loans		Cash		Other Assets, Net			Total
Secured Borrowings — VIEs:
FFELP Loan securitizations	$	—	$	54,697		$	54,697		$	55,535	$	1,606	$	1,438		$	58,579
Private Education Loan securitizations		960		13,891			14,851			15,823		606		187			16,616
FFELP Loan ABCP facilities		2,053		479			2,532			2,533		36		76			2,645
Private Education Loan ABCP facilities		2,582		—			2,582			2,835		74		27			2,936
Total before hedge accounting adjustments		5,595		69,067			74,662			76,726		2,322		1,728			80,776
Hedge accounting adjustments		—		(167	)		(167	)		—		—		(308	)		(308	)
Total	$	5,595	$	68,900		$	74,495		$	76,726	$	2,322	$	1,420		$	80,468

	December 31, 2019
	Debt Outstanding								Carrying Amount of Assets Securing Debt Outstanding
(Dollars in millions)	Short Term		Long Term			Total			Loans		Cash		Other Assets, Net			Total
Secured Borrowings — VIEs:
FFELP Loan securitizations	$	72	$	59,735		$	59,807		$	60,834	$	1,833	$	1,400		$	64,067
Private Education Loan securitizations		2,120		11,430			13,550			15,412		509		152			16,073
FFELP Loan ABCP facilities		2,783		617			3,400			3,421		63		102			3,586
Private Education Loan ABCP facilities		2,114		1,513			3,627			4,197		101		28			4,326
Total before hedge accounting adjustments		7,089		73,295			80,384			83,864		2,506		1,682			88,052
Hedge accounting adjustments		—		(439	)		(439	)		—		—		(593	)		(593	)
Total	$	7,089	$	72,856		$	79,945		$	83,864	$	2,506	$	1,089		$	87,459

Summary of Activity Related to Senior Unsecured Debt Repurchases

The following table summarizes activity related to our senior unsecured debt repurchases.

	Years Ended December 31,
(Dollars in millions)	2020			2019		2018
Debt principal repurchased	$	768		$	1,184	$	2,809
Gains (losses) on debt repurchases	$	(6	)	$	45	$	19

- Definition

Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide.

+ References + Details

Borrowings - Company's Borrowings (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Short-term borrowings	$ 6,613	$ 8,483
Short-term Weighted Average Interest Rate	1.97%	3.42%
Long-term borrowings	$ 77,332	$ 81,715
Long-term Weighted Average Interest Rate	1.62%	2.96%
Total	$ 83,945	$ 90,198
FFELP Loan ABCP Facilities [Member]
Debt Instrument [Line Items]
Total	2,500
Private Education Loan ABCP Facilities [Member]
Debt Instrument [Line Items]
Total	2,600
Total Before Hedge Accounting Adjustments [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 6,609	$ 8,479
Short-term Weighted Average Interest Rate	1.97%	3.42%
Long-term borrowings	$ 76,781	$ 81,756
Long-term Weighted Average Interest Rate	1.63%	2.96%
Total	$ 83,390	$ 90,235
Total Before Hedge Accounting Adjustments [Member] \| Senior Unsecured Debt [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 677	$ 1,052
Short-term Weighted Average Interest Rate	6.61%	6.45%
Long-term borrowings	$ 7,714	$ 8,461
Long-term Weighted Average Interest Rate	6.19%	6.30%
Total	$ 8,391	$ 9,513
Total Before Hedge Accounting Adjustments [Member] \| Total Unsecured Borrowings [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 677	$ 1,052
Short-term Weighted Average Interest Rate	6.61%	6.45%
Long-term borrowings	$ 7,714	$ 8,461
Long-term Weighted Average Interest Rate	6.19%	6.30%
Total	$ 8,391	$ 9,513
Total Before Hedge Accounting Adjustments [Member] \| FFELP Loan Securitizations [Member]
Debt Instrument [Line Items]
Short-term borrowings		$ 72
Short-term Weighted Average Interest Rate		3.16%
Long-term borrowings	$ 54,697	$ 59,735
Long-term Weighted Average Interest Rate	0.89%	2.45%
Total	$ 54,697	$ 59,807
Total Before Hedge Accounting Adjustments [Member] \| Private Education Loan Securitizations [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 960	$ 2,120
Short-term Weighted Average Interest Rate	2.68%	4.14%
Long-term borrowings	$ 13,891	$ 11,430
Long-term Weighted Average Interest Rate	2.04%	3.12%
Total	$ 14,851	$ 13,550
Total Before Hedge Accounting Adjustments [Member] \| FFELP Loan ABCP Facilities [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 2,053	$ 2,783
Short-term Weighted Average Interest Rate	1.05%	2.46%
Long-term borrowings	$ 479	$ 617
Long-term Weighted Average Interest Rate	1.13%	2.66%
Total	$ 2,532	$ 3,400
Total Before Hedge Accounting Adjustments [Member] \| Private Education Loan ABCP Facilities [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 2,582	$ 2,114
Short-term Weighted Average Interest Rate	1.46%	2.76%
Long-term borrowings		$ 1,513
Long-term Weighted Average Interest Rate		3.31%
Total	$ 2,582	$ 3,627
Total Before Hedge Accounting Adjustments [Member] \| Other [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 337	$ 338
Short-term Weighted Average Interest Rate	0.09%	1.55%
Total	$ 337	$ 338
Total Before Hedge Accounting Adjustments [Member] \| Secured Borrowings [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 5,932	$ 7,427
Short-term Weighted Average Interest Rate	1.44%	2.99%
Long-term borrowings	$ 69,067	$ 73,295
Long-term Weighted Average Interest Rate	1.12%	2.58%
Total	$ 74,999	$ 80,722
Hedge Accounting Adjustments [Member]
Debt Instrument [Line Items]
Short-term borrowings	4	4
Long-term borrowings	$ 551	(41)
Long-term Weighted Average Interest Rate	(0.01%)
Total	$ 555	$ (37)

Allowance for Loan Losses (Tables)

12 Months Ended

Dec. 31, 2020

Financing Receivable Allowance For Credit Losses [Line Items]

Allowance for Credit Losses and Recorded Investments in Loans

Allowance for Loan Losses Metrics

	Year Ended December 31, 2020
(Dollars in millions)	FFELP Loans			Private Education Loans			Total
Allowance at beginning of period (after transition adjustment to CECL on January 1, 2020)	$	324		$	1,045		$	1,369
Total provision		13			142			155
Charge-offs:
Net adjustment resulting from the change in the charge-off rate⁽¹⁾		—			(23	)		(23	)
Net charge-offs remaining⁽²⁾		(49	)		(184	)		(233	)
Total charge-offs⁽²⁾		(49	)		(207	)		(256	)
Decrease in expected future recoveries on charged-off loans⁽³⁾		—			109			109
Allowance at end of period		288			1,089			1,377
Plus: expected future recoveries on charged-off loans⁽³⁾		—			479			479
Allowance at end of period excluding expected future recoveries on charged-off loans⁽⁴⁾	$	288		$	1,568		$	1,856
Net charge-offs as a percentage of average loans in repayment, excluding the net adjustment resulting from the change in the charge-off rate⁽¹⁾		.10	%		.88	%
Net adjustment resulting from the change in charge-off rate as a percentage of average loans in repayment⁽¹⁾		—	%		.11	%
Allowance coverage of charge-offs⁽⁴⁾		5.9			7.6
Allowance as a percentage of the ending total loan balance⁽⁴⁾		.5	%		7.1	%
Allowance as a percentage of the ending loans in repayment⁽⁴⁾		.6	%		7.5	%
Ending total loans	$	58,572		$	22,168
Average loans in repayment	$	48,130		$	20,790
Ending loans in repayment	$	48,057		$	20,841

⁽¹⁾	In 2020, the portion of the loan amount charged off at default on Private Education Loans increased from 81% to 81.4%. This charge resulted in a $23 million reduction to the balance of the receivable for partially charged-off loan balance.

⁽²⁾

Charge-offs are reported net of expected recoveries. For Private Education Loans, at the time of charge-off, the expected recovery amount is transferred from the education loan balance to the allowance for loan loss and is referred to as the expected future recoveries on charged-off loans. For FFELP Loans, the recovery is received at the time of charge-off.

⁽³⁾

At the end of each month, for Private Education Loans that are 212 or more days past due, we charge off the estimated loss of a defaulted loan balance. Actual recoveries are applied against the remaining loan balance that was not charged off. We refer to this as the “expected future recoveries on charged-off loans.” If actual periodic recoveries are less than expected, the difference is immediately charged off through the allowance for Private Education Loan losses with an offsetting reduction in the expected future recoveries for charged-off loans. If actual periodic recoveries are greater than expected, they will be reflected as a recovery through the allowance for Private Education Loan losses once the cumulative recovery amount exceeds the cumulative amount originally expected to be recovered. The following table summarizes the activity in the expected future recoveries on charged-off loans:

	Year Ended December 31,
(Dollars in millions)	2020
Beginning of period expected recoveries	$	588
Expected future recoveries of current period defaults		32
Recoveries		(107	)
Charge-offs		(34	)
End of period expected recoveries	$	479
Change in balance during period	$	(109	)

⁽⁴⁾	The allowance used for these metrics excludes the expected future recoveries on charged-off loans to better reflect the current expected credit losses remaining in the portfolio.

	Year Ended December 31, 2019
(Dollars in millions)	FFELP Loans			Private Education Loans			Other Loans			Total
Beginning balance	$	76		$	1,201		$	9		$	1,286
Total provision		30			226			1			258
Net adjustment resulting from the change in the charge-off rate⁽¹⁾		—			(21	)		—			(21	)
Net charge-offs remaining⁽²⁾		(42	)		(364	)		(2	)		(408	)
Total net charge-offs		(42	)		(385	)		(2	)		(429	)
Reclassification of interest reserve⁽³⁾		—			7			—			7
Loan sales		—			(1	)		(8	)		(9	)
Ending balance	$	64		$	1,048		$	—		$	1,112
Allowance Ending Balance:
Individually evaluated for impairment — TDR	$	—		$	941		$	—		$	941
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans		64			107			—			171
Purchased Non-Credit Impaired Loans acquired at a discount⁽⁴⁾		—			—			—			—
Purchased Credit Impaired Loans⁽⁴⁾		—			—			—			—
Ending total allowance	$	64		$	1,048		$	—		$	1,112
Loans Ending Balance:
Individually evaluated for impairment — TDR	$	—		$	9,617		$	—		$	9,617
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans		61,589			12,286			9			73,884
Purchased Non-Credit Impaired Loans acquired at a discount⁽⁴⁾		2,505			1,806			—			4,311
Purchased Credit Impaired Loans⁽⁴⁾		—			201			—			201
Ending total loans⁽⁵⁾	$	64,094		$	23,910		$	9		$	88,013
Net charge-offs as a percentage of average loans in repayment, excluding the net adjustment resulting from the change in the charge-off rate⁽¹⁾		.07	%		1.67	%		—	%
Net adjustment resulting from the change in charge-off rate as a percentage of average loans in repayment⁽¹⁾		—	%		.10	%		—	%
Allowance coverage of charge-offs		1.5			2.7			—
Allowance as a percentage of the ending total loan balance		.10	%		4.38	%		—	%
Allowance as a percentage of the ending loans in repayment		.12	%		4.74	%		—	%
Ending total loans⁽⁵⁾	$	64,094		$	23,910		$	9
Average loans in repayment	$	55,978		$	21,859		$	29
Ending loans in repayment	$	53,538		$	22,089		$	9

⁽¹⁾

In 2019, the portion of the loan amount charged off at default on Private Education Loans increased from 80.5% to 81%. This charge resulted in a $21 million reduction to the balance of the receivable for partially charged-off loan balance.

₍₂₎

Charge-offs are reported net of expected recoveries. For Private Education Loans, the expected recovery amount is transferred to the receivable for partially charged-off loan balance. Charge-offs include charge-offs against the receivable for partially charged-off loans which represents the difference between what was expected to be recovered and any shortfalls in what was actually recovered in the period. For FFELP Loans, the recovery is received at the time of charge-off.

⁽³⁾

Represents the additional allowance related to the amount of uncollectible interest reserved within interest income that is transferred in the period to the allowance for loan losses when interest is capitalized to a loan’s principal balance.

⁽⁴⁾

The Purchased Credit Impaired Loans’ losses are not provided for by the allowance for loan losses in the above table as these loans are separately reserved for, if needed. No allowance for loan losses has been established for these loans as of December 31, 2019. The losses of the Purchased Non-Credit Impaired Loans acquired at a discount are not provided for by the allowance for loan losses in the above table as the remaining purchased discount associated with the FFELP and Private Education Loans of $33 million and $268 million respectively, as of December 31, 2019 is greater than the incurred losses and as a result no allowance for loan losses has been established for these loans as of December 31, 2019.

⁽⁵⁾

Ending total loans for Private Education Loans includes the receivable for partially charged-off loans.

	Year Ended December 31, 2018
(Dollars in millions)	FFELP Loans			Private Education Loans			Other Loans			Total
Allowance for Loan Losses
Beginning balance	$	60		$	1,297		$	10		$	1,367
Total provision		70			299			1			370
Net adjustment resulting from the change in the charge- off rate⁽¹⁾		—			(32	)		—			(32	)
Net charge-offs remaining⁽²⁾		(54	)		(371	)		(2	)		(427	)
Total net charge-offs		(54	)		(403	)		(2	)		(459	)
Reclassification of interest reserve⁽³⁾		—			8			—			8
Ending balance	$	76		$	1,201		$	9		$	1,286
Allowance Ending Balance:
Individually evaluated for impairment — TDR	$	—		$	1,100		$	8		$	1,108
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans		76			101			1			178
Purchased Non-Credit Impaired Loans acquired at a discount⁽⁴⁾		—			—			—			—
Purchased Credit Impaired Loans⁽⁴⁾		—			—			—			—
Ending total allowance	$	76		$	1,201		$	9		$	1,286
Loans Ending Balance:
Individually evaluated for impairment — TDR	$	—		$	10,336		$	28		$	10,364
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans		68,880			11,464			51			80,395
Purchased Non-Credit Impaired Loans acquired at a discount⁽⁴⁾		2,850			2,180			—			5,030
Purchased Credit Impaired Loans⁽⁴⁾		—			225			—			225
Ending total loans⁽⁵⁾	$	71,730		$	24,205		$	79		$	96,014
Net charge-offs as a percentage of average loans in repayment, excluding the net adjustment resulting from the change in the charge-off rate⁽¹⁾		.09	%		1.66	%		—	%
Net adjustment resulting from the change in charge-off rate as a percentage of average loans in repayment⁽¹⁾		—	%		.14	%		—	%
Allowance coverage of charge-offs		1.4			3.0			—
Allowance as a percentage of the ending total loan balance		.11	%		4.96	%		11.52	%
Allowance as a percentage of the ending loans in repayment		.13	%		5.45	%		11.52	%
Ending total loans⁽⁵⁾	$	71,730		$	24,205		$	79
Average loans in repayment	$	62,927		$	22,312		$	75
Ending loans in repayment	$	59,551		$	22,037		$	79

⁽¹⁾

In 2018, the portion of the loan amount charged off at default on Private Education Loans increased from 79% to 80.5%. This charge resulted in a $32 million reduction to the balance of the receivable for partially charged-off loan balance.

⁽²⁾

⁽³⁾

⁽⁴⁾

The Purchased Credit Impaired Loans’ losses are not provided for by the allowance for loan losses in the above table as these loans are separately reserved for, if needed. No allowance for loan losses has been established for these loans as of December 31, 2018. The losses of the Purchased Non-Credit Impaired Loans acquired at a discount are not provided for by the allowance for loan losses in the above table as the remaining purchased discount associated with the FFELP and Private Education Loans of $37 million and $326 million respectively, as of December 31, 2018 is greater than the incurred losses and as a result no allowance for loan losses has been established for these loans as of December 31, 2018.

⁽⁵⁾

Ending total loans for Private Education Loans includes the receivable for partially charged-off loans.

Loans Modified Accounts for TDR

The following table provides the amount of loans modified in the periods presented that resulted in a TDR. Additionally, the table summarizes charge-offs occurring in the TDR portfolio, as well as TDRs for which a payment default occurred in the current period within 12 months of the loan first being designated as a TDR. We define payment default as 60 days past due for this disclosure.

	Years Ended December 31,
(Dollars in millions)	2020		2019		2018
Modified loans⁽¹⁾	$	264	$	475	$	596
Charge-offs⁽²⁾	$	157	$	324	$	343
Payment default	$	47	$	109	$	142

⁽¹⁾ Represents period ending balance of loans that have been modified during the period and resulted in a TDR.

⁽²⁾ Represents loans that charged off that were classified as TDRs.

Age Analysis of Past Due Loans Delinquencies

	FFELP Loan Delinquencies
	December 31, 2020						December 31, 2019
(Dollars in millions)	Balance			%			Balance			%
Loans in-school/grace/deferment⁽¹⁾	$	2,791					$	3,114
Loans in forbearance⁽²⁾		7,725						7,442
Loans in repayment and percentage of each status:
Loans current		43,623			90.8	%		47,255			88.3	%
Loans delinquent 31-60 days⁽³⁾		1,374			2.9			2,094			3.9
Loans delinquent 61-90 days⁽³⁾		836			1.7			1,082			2.0
Loans delinquent greater than 90 days⁽³⁾		2,223			4.6			3,107			5.8
Total FFELP Loans in repayment		48,056			100	%		53,538			100	%
Total FFELP Loans, gross		58,572						64,094
FFELP Loan unamortized premium⁽⁴⁾		—						545
Total FFELP Loans		58,572						64,639
FFELP Loan allowance for losses		(288	)					(64	)
FFELP Loans, net	$	58,284					$	64,575
Percentage of FFELP Loans in repayment					82.0	%					83.5	%
Delinquencies as a percentage of FFELP Loans in repayment					9.2	%					11.7	%
FFELP Loans in forbearance as a percentage of loans in repayment and forbearance					13.8	%					12.2	%

⁽¹⁾

Loans for customers who may still be attending school or engaging in other permitted educational activities and are not yet required to make payments on their loans, e.g., residency periods for medical students or a grace period for bar exam preparation, as well as loans for customers who have requested and qualify for other permitted program deferments such as military, unemployment, or economic hardships.

⁽²⁾

Loans for customers who have used their allowable deferment time or do not qualify for deferment, that need additional time to obtain employment or who have temporarily ceased making full payments due to hardship or other factors such as disaster relief, including COVID-19 relief programs, consistent with established loan program servicing policies and procedures.

⁽³⁾	The period of delinquency is based on the number of days scheduled payments are contractually past due.

⁽⁴⁾	In connection with the adoption of CECL on January 1, 2020, the $497 million premium as of December 31, 2020, associated with the loans is now included as part of the respective loan balance for this disclosure. This change is prospective in nature as prior balances are not restated under CECL.

	Private Education Loan Delinquencies
	TDRs
	December 31, 2020						December 31, 2019
(Dollars in millions)	Balance			%			Balance			%
Loans in-school/grace/deferment⁽¹⁾	$	280					$	349
Loans in forbearance⁽²⁾		703						479
Loans in repayment and percentage of each status:
Loans current		6,952			93.4	%		7,557			89.5	%
Loans delinquent 31-60 days⁽³⁾		185			2.5			296			3.5
Loans delinquent 61-90 days⁽³⁾		114			1.5			191			2.3
Loans delinquent greater than 90 days⁽³⁾		197			2.6			398			4.7
Total TDR loans in repayment		7,448			100	%		8,442			100	%
Total TDR loans, gross		8,431						9,270
TDR loans unamortized discount⁽⁴⁾		—						(203	)
Total TDR loans		8,431						9,067
TDR loans receivable for partially charged-off loans⁽⁴⁾		—						347
TDR loans allowance for losses		(929	)					(941	)
TDR loans, net	$	7,502					$	8,473
Percentage of TDR loans in repayment					88.3	%					91.1	%
Delinquencies as a percentage of TDR loans in repayment					6.6	%					10.5	%
Loans in forbearance as a percentage of TDR loans in repayment and forbearance					8.6	%					5.4	%

⁽¹⁾	Deferment includes customers who have returned to school or are engaged in other permitted educational activities and are not yet required to make payments on their loans, e.g., residency periods for medical students or a grace period for bar exam preparation.

⁽²⁾

Loans for customers who have requested extension of grace period generally during employment transition or who have temporarily ceased making full payments due to hardship or other factors such as disaster relief, including COVID-19 relief programs, consistent with established loan program servicing policies and procedures.

⁽³⁾	The period of delinquency is based on the number of days scheduled payments are contractually past due.

⁽⁴⁾

In connection with the adoption of CECL on January 1, 2020, (1) the $200 million discount as of December 31, 2020, associated with the loans is now included as part of the respective loan balance for this disclosure and (2) the receivable for partially charged-off loans balance has been reclassified from the Private Education Loan balance to the allowance for loan loss. Both of these changes are prospective in nature as prior balances are not restated under CECL.

	Private Education Loan Delinquencies
	Non-TDRs
	December 31, 2020						December 31, 2019
(Dollars in millions)	Balance			%			Balance			%
Loans in-school/grace/deferment⁽¹⁾	$	203					$	280
Loans in forbearance⁽²⁾		141						125
Loans in repayment and percentage of each status:
Loans current		13,335			99.6	%		13,526			99.1	%
Loans delinquent 31-60 days⁽³⁾		26			.2			53			.4
Loans delinquent 61-90 days⁽³⁾		12			.1			27			.2
Loans delinquent greater than 90 days⁽³⁾		20			.1			41			.3
Total non-TDR loans in repayment		13,393			100	%		13,647			100	%
Total non-TDR loans, gross		13,737						14,052
Non-TDR loans unamortized discount⁽⁴⁾		—						(414	)
Total non-TDR loans		13,737						13,638
Non-TDR loans receivable for partially charged-off loans⁽⁴⁾		—						241
Non-TDR loans allowance for losses		(160	)					(107	)
Non-TDR loans, net	$	13,577					$	13,772
Percentage of non-TDR loans in repayment					97.5	%					97.1	%
Delinquencies as a percentage of non-TDR loans in repayment					.4	%					.9	%
Loans in forbearance as a percentage of non-TDR loans in repayment and forbearance					1.0	%					.9	%

⁽¹⁾	Deferment includes customers who have returned to school or are engaged in other permitted educational activities and are not yet required to make payments on their loans, e.g., residency periods for medical students or a grace period for bar exam preparation.

⁽²⁾

⁽³⁾	The period of delinquency is based on the number of days scheduled payments are contractually past due.

⁽⁴⁾

In connection with the adoption of CECL on January 1, 2020, (1) the $275 million discount as of December 31, 2020, associated with the loans is now included as part of the respective loan balance for this disclosure and (2) the receivable for partially charged-off loans balance has been reclassified from the Private Education Loan balance to the allowance for loan loss. Both of these changes are prospective in nature as prior balances are not restated under CECL.

Loans Type

Loan type:

(Dollars in millions)	December 31, 2020		December 31, 2019		Change
Stafford Loans	$	17,686	$	19,093	$	(1,407	)
Consolidation Loans		35,968		39,706		(3,738	)
Rehab Loans		4,918		5,295		(377	)
Total loans, gross	$	58,572	$	64,094	$	(5,522	)

Private Education Loans [Member]

Financing Receivable Allowance For Credit Losses [Line Items]

Private Education Loan Portfolio Stratified by Key Credit Quality Indicators

	Private Education Loan Credit Quality Indicators by Origination Year
(Dollars in millions)	2020		2019		2018		2017		2016		Prior		Total			% of Total
Credit Quality Indicators
FICO Scores:
640 and above	$	4,008	$	2,964	$	1,079	$	340	$	72	$	11,746	$	20,209			91	%
Below 640		15		34		23		9		2		1,876		1,959			9
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
Loan Status:
In-school/grace/ deferment/forbearance	$	23	$	43	$	25	$	10	$	2	$	1,224	$	1,327			6	%
Current/90 days or less delinquent		3,999		2,953		1,075		338		72		12,187		20,624			93
Greater than 90 days delinquent		1		2		2		1		—		211		217			1
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
Seasoning⁽¹⁾:
1-12 payments	$	4,014	$	879	$	7	$	2	$	—	$	180	$	5,082			23	%
13-24 payments		—		2,098		243		7		1		234		2,583		12
25-36 payments		—		—		839		101		3		380		1,323			6
37-48 payments		—		—		—		236		38		584		858		4
More than 48 payments		—		—		—		—		31		11,808		11,839			53
Loans in-school/ grace/deferment		9		21		13		3		1		436		483		2
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
TDR Status:
TDR	$	1	$	14	$	23	$	31	$	11	$	8,351	$	8,431			38	%
Non-TDR		4,022		2,984		1,079		318		63		5,271		13,737			62
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
Cosigners:
With cosigner⁽²⁾	$	5	$	13	$	1	$	49	$	21	$	8,911	$	9,000			41	%
Without cosigner		4,018		2,985		1,101		300		53		4,711		13,168			59
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
School Type:
Not-for-profit	$	3,844	$	2,801	$	1,019	$	333	$	74	$	11,255	$	19,326			87	%
For-profit		179		197		83		16		—		2,367		2,842			13
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
Allowance for loan losses														(1,089	)
Total loans, net													$	21,079

⁽¹⁾	Number of months in active repayment for which a scheduled payment was received.

⁽²⁾	Excluding Private Education Refinance Loans, which do not have a cosigner, the cosigner rate was 65% for total loans at December 31, 2020

	Private Education Loan Credit Quality Indicators
	December 31, 2019
	TDRs					Non-TDRs
(Dollars in millions)	Balance⁽³⁾		% of Balance			Balance⁽³⁾		% of Balance
Credit Quality Indicators
Original Winning FICO Scores:
FICO 640 and above	$	8,493		92	%	$	13,687		97	%
FICO below 640		777		8			365		3
Total	$	9,270		100	%	$	14,052		100	%
School Type:
Not-for-profit	$	7,387		80	%	$	12,614		90	%
For-profit		1,883		20			1,438		10
Total	$	9,270		100	%	$	14,052		100	%
Cosigners:
With cosigner⁽¹⁾	$	5,792		62	%	$	5,184		37	%
Without cosigner		3,478		38			8,868		63
Total	$	9,270		100	%	$	14,052		100	%
Seasoning⁽²⁾:
1-12 payments	$	224		3	%	$	4,673		33	%
13-24 payments		301		3			1,570		11
25-36 payments		472		5			603		4
37-48 payments		662		7			251		2
More than 48 payments		7,262		78			6,675		48
Loans in-school/grace/deferment		349		4			280		2
Total loans, gross	$	9,270		100	%	$	14,052		100	%

⁽¹⁾	Excluding Private Education Refinance Loans, which do not have a cosigner, the cosigner rate was 63% and 67% for TDRs and non-TDRs, respectively, at December 31, 2019.

⁽²⁾	Number of months in active repayment for which a scheduled payment was received.

⁽³⁾	Balance equals the gross Private Education Loans.

Segment Reporting - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) Client Segment	Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable operating segments \| Segment	4
Total assets	$ 87,412	$ 94,903
Business Processing [Member]
Segment Reporting Information [Line Items]
Total assets	$ 425	423
Business Processing [Member] \| Minimum [Member]
Segment Reporting Information [Line Items]
Number of clients for business processing services \| Client	500
Other Segment [Member]
Segment Reporting Information [Line Items]
Total assets	$ 1,900	$ 1,600

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=121559654&loc=d3e5710-111685

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=116870748&loc=SL6758485-165988

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8906-108599

+ Details

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Open Market Repurchases [Member]	Derivative Contract Settlement [Member]	Common Stock [Member]	Treasury Stock [Member]	Treasury Stock [Member] Open Market Repurchases [Member]	Treasury Stock [Member] Derivative Contract Settlement [Member]	Common Stock Shares Outstanding [Member]	Common Stock Shares Outstanding [Member] Open Market Repurchases [Member]	Common Stock Shares Outstanding [Member] Derivative Contract Settlement [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment	Total Stockholders' Equity [Member]	Total Stockholders' Equity [Member] Cumulative Effect, Period of Adoption, Adjustment	Total Stockholders' Equity [Member] Open Market Repurchases [Member]	Total Stockholders' Equity [Member] Derivative Contract Settlement [Member]	Noncontrolling Interest [Member]
Beginning Balance, Value at Dec. 31, 2017	$ 3,485				$ 4	$ (2,692)						$ 3,077	$ 61	$ 3,004		$ 3,454				$ 31
Beginning Balance, Shares at Dec. 31, 2017					439,718,145	(176,667,573)			263,050,572
Comprehensive income:
Net income	395													395		395
Other comprehensive income (loss), net of tax	39												39			39
Total comprehensive income	434															434
Cash dividends:
Common stock	(166)													(166)		(166)
Dividend equivalent units related to employee stock-based compensation plans	(2)													(2)		(2)
Issuance of common shares	$ 43											43				43
Issuance of common shares, Shares	5,700,000				5,659,681				5,659,681
Stock-based compensation expense	$ 25											25				25
Repurchase of common stock:
Common stock repurchased			$ (160)	$ (60)			$ (160)	$ (60)	$ (220)									$ (160)	$ (60)
Common stock repurchased, Shares							(13,131,159)	(4,312,192)	(17,400,000)	(13,131,159)	(4,312,192)
(Gain)/loss on settlement	4					$ 4										4
Shares repurchased related to employee stock-based compensation plans	$ (53)					$ (53)										(53)
Shares repurchased related to employee stock-based compensation plans, Shares	(3,800,000)					(3,829,629)			(3,829,629)
Purchase of noncontrolling interest	$ (3)																			(3)
Reclassification from adoption of ASU No. 2018-02													13	(13)
Ending Balance, Value at Dec. 31, 2018	3,547				$ 4	$ (2,961)						3,145	113	3,218		3,519				28
Ending Balance, Shares at Dec. 31, 2018					445,377,826	(197,940,553)			247,437,273
Comprehensive income:
Net income	597													597		597
Other comprehensive income (loss), net of tax	(204)												(204)			(204)
Total comprehensive income	393															393
Cash dividends:
Common stock	(147)													(147)		(147)
Dividend equivalent units related to employee stock-based compensation plans	(4)													(4)		(4)
Issuance of common shares	$ 28											28				28
Issuance of common shares, Shares	5,700,000				5,717,053				5,717,053
Stock-based compensation expense	$ 25											25				25
Repurchase of common stock:
Common stock repurchased			(440)				$ (440)		$ (440)									(440)
Common stock repurchased, Shares							(34,491,342)		(34,500,000)	(34,491,342)
Shares repurchased related to employee stock-based compensation plans	$ (38)					$ (38)										(38)
Shares repurchased related to employee stock-based compensation plans, Shares	(3,200,000)					(3,226,301)			(3,226,301)
Net activity in noncontrolling interest	$ (15)																			(15)
Ending Balance, Value at Dec. 31, 2019	3,349	$ (620)			$ 4	$ (3,439)						3,198	(91)	3,664	$ (620)	3,336	$ (620)			13
Ending Balance, Shares at Dec. 31, 2019					451,094,879	(235,658,196)			215,436,683
Repurchase of common stock:
Accounting Standards Update [Extensible List]		us-gaap:AccountingStandardsUpdate201613Member
Net income	412													412		412
Other comprehensive income (loss), net of tax	(183)												(183)			(183)
Total comprehensive income	229															229
Common stock	(123)													(123)		(123)
Dividend equivalent units related to employee stock-based compensation plans	(2)													(2)		(2)
Issuance of common shares	$ 10											10				10
Issuance of common shares, Shares	2,700,000				2,684,096				2,684,096
Stock-based compensation expense	$ 18											18				18
Common stock repurchased			$ (400)				$ (400)		$ (400)									$ (400)
Common stock repurchased, Shares							(30,628,580)		(30,600,000)	(30,628,580)
Shares repurchased related to employee stock-based compensation plans	$ (15)					$ (15)										(15)
Shares repurchased related to employee stock-based compensation plans, Shares	(1,200,000)					(1,189,745)			(1,189,745)
Net activity in noncontrolling interest	$ 1																			1
Ending Balance, Value at Dec. 31, 2020	$ 2,447				$ 4	$ (3,854)						$ 3,226	$ (274)	$ 3,331		$ 2,433				$ 14
Ending Balance, Shares at Dec. 31, 2020					453,778,975	(267,476,521)			186,302,454

Significant Accounting Policies - Summary of Translation Adjustments in Connection with Adopting CECL (Detail) - USD ($) $ in Millions		12 Months Ended
	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Allowance at beginning of period	$ 1,112	$ 1,112	$ 1,286	$ 1,367
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses		155	258	370
Allowance at end of period		1,377	1,112	1,286
ASU 2016-13 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Allowance at beginning of period	1,369	1,369
Transition adjustments made under CECL on January 1, 2020:
Reclassification of the expected future recoveries on charged-off loans	(588)
Net increase to allowance for loan losses under CECL	257
Allowance at end of period	1,369		1,369
ASU 2016-13 [Member] \| Non-PCD Portfolio [Member]
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses	802
ASU 2016-13 [Member] \| PCD Portfolio [Member]
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses	43
FFELP Loans [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Allowance at beginning of period	64	64	76	60
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses		13	30	70
Allowance at end of period		288	64	76
FFELP Loans [Member] \| ASU 2016-13 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Allowance at beginning of period	324	324
Transition adjustments made under CECL on January 1, 2020:
Net increase to allowance for loan losses under CECL	260
Allowance at end of period	324		324
FFELP Loans [Member] \| ASU 2016-13 [Member] \| Non-PCD Portfolio [Member]
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses	260
Private Education Loans [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Allowance at beginning of period	1,048	1,048	1,201	1,297
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses		142	226	299
Reclassification of the expected future recoveries on charged-off loans		(107)
Allowance at end of period		1,089	1,048	$ 1,201
Private Education Loans [Member] \| PCD Portfolio [Member]
Transition adjustments made under CECL on January 1, 2020:
Allowance at end of period	43
Private Education Loans [Member] \| ASU 2016-13 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Allowance at beginning of period	1,045	$ 1,045
Transition adjustments made under CECL on January 1, 2020:
Reclassification of the expected future recoveries on charged-off loans	(588)
Net increase to allowance for loan losses under CECL	(3)
Allowance at end of period	1,045		$ 1,045
Private Education Loans [Member] \| ASU 2016-13 [Member] \| Non-PCD Portfolio [Member]
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses	542
Private Education Loans [Member] \| ASU 2016-13 [Member] \| PCD Portfolio [Member]
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses	$ 43

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2020

Equity [Abstract]

Common Share Repurchases, Issuances and Dividends Paid

The following table summarizes our common share repurchases, issuances and dividends paid.

	Years Ended December 31,
(Dollars and shares in millions, except per share amounts)	2020		2019		2018
Common stock repurchased⁽¹⁾		30.6		34.5		17.4
Common stock repurchased (in dollars)⁽¹⁾	$	400	$	440	$	220
Average purchase price per share⁽¹⁾	$	13.06	$	12.76	$	12.64
Remaining common stock repurchase authority⁽¹⁾	$	600	$	1,000	$	440
Shares repurchased related to employee stock-based compensation plans⁽²⁾		1.2		3.2		3.8
Average purchase price per share⁽²⁾	$	12.86	$	11.62	$	13.71
Common shares issued⁽³⁾		2.7		5.7		5.7
Dividends paid	$	123	$	147	$	166
Dividends per share	$	.64	$	.64	$	.64

⁽¹⁾

⁽²⁾

Comprises shares withheld from stock option exercises and vesting of restricted stock for employees’ tax withholding obligations and shares tendered by employees to satisfy option exercise costs.

⁽³⁾

Common shares issued under our various compensation and benefit plans.

Fair Value Measurements - Fair Values of Financial Assets and Liabilities, Including Derivative Financial Instruments (Parenthetical) (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total interest-bearing liabilities, fair value	$ 83,345	$ 89,815
Difference [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total interest-bearing liabilities, fair value	600	383
Senior Unsecured Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amount of asset-backed securitization repurchase facility	8,400
Senior Unsecured Debt [Member] \| Difference [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total interest-bearing liabilities, fair value	$ 371	$ 56

Education Loans - Additional Information (Detail)	12 Months Ended
Education Loans - Additional Information (Detail)	Dec. 31, 2020	Dec. 31, 2019
Accounts Notes And Loans Receivable [Line Items]
Percentage of education loan portfolio in repayment	85.00%	87.00%
After October 1 1993 and before July 1 2006 [Member] \| FFELP Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Percentage reimbursement on all qualifying default claims period	98.00%
On or After July 1 2006 [Member] \| FFELP Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Percentage reimbursement on all qualifying default claims period	97.00%
Weighted Average [Member]
Accounts Notes And Loans Receivable [Line Items]
Estimated weighted average life of education loans	6 years	6 years
Stafford Loans [Member] \| Minimum [Member] \| FFELP Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Repayment term	5 years
Stafford Loans [Member] \| Maximum [Member] \| FFELP Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Repayment term	10 years
Consolidation Loans [Member] \| Minimum [Member] \| FFELP Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Repayment term	12 years
Consolidation Loans [Member] \| Maximum [Member] \| FFELP Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Repayment term	30 years
Private Education Loans [Member] \| Minimum [Member]
Accounts Notes And Loans Receivable [Line Items]
Repayment term	10 years
Private Education Loans [Member] \| Maximum [Member]
Accounts Notes And Loans Receivable [Line Items]
Repayment term	15 years

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Maximum remaining term for investment purchased for estimating at cost	90 days
Decrease in valuation due to net credit risk adjustments	$ 8	$ 11
Decrease in valuation due to liquidity adjustments	$ 5	$ 12

Revenue from Contracts with Customers Accounted for in Accordance with ASC 606 - Additional Information (Detail) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Accounts receivable	$ 118,000,000	$ 119,000,000
ASU 2014-09 [Member]
Disaggregation Of Revenue [Line Items]
Accounts receivable	90,000,000	$ 67,000,000
Contract assets	0
Contract liability	$ 0

Derivative Financial Instruments - Additional Information (Detail) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Net positive exposure related to corporate derivatives	$ 13,000,000	$ 12,000,000
Euro and British Pound Sterling denominated bonds outstanding in securitization trusts	3,600,000,000
Notional of interest rate swaps entered into by the trusts to swap Prime to LIBOR	71,700,000,000	104,400,000,000
Net positive exposure on foreign currency swaps	28,000,000	0
Decrease in valuation due to net credit risk adjustments	8,000,000	11,000,000
Decrease in valuation due to liquidity adjustments	5,000,000	12,000,000
Derivative liability at fair value including accrued interest and premium receivable	504,000,000	658,000,000
Counterparty [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative liability at fair value including accrued interest and premium receivable	164,000,000
Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional of interest rate swaps entered into by the trusts to swap Prime to LIBOR	51,000,000,000.0	$ 79,200,000,000
Interest Rate Swaps [Member] \| Assets and Liabilities of Consolidated Variable Interest Entities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional of interest rate swaps entered into by the trusts to swap Prime to LIBOR	$ 2,400,000,000

Segment Reporting - Asset Information for Loans Segment (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Loans, net	$ 79,363	$ 86,820
Other	3,492	3,334
Total assets	87,412	94,903
Federal Education Loans [Member]
Segment Reporting Information [Line Items]
Loans, net	58,284	64,575
Cash and investments	1,685	2,043
Other	2,241	2,202
Total assets	62,210	68,820
Consumer Lending [Member]
Segment Reporting Information [Line Items]
Loans, net	21,079	22,245
Cash and investments	828	927
Other	964	931
Total assets	$ 22,871	$ 24,103

- Definition

+ References

+ Details

Revenue from Contracts with Customers Accounted for in Accordance with ASC 606 (Tables)

12 Months Ended

Dec. 31, 2020

Revenue From Contract With Customer [Abstract]

Summary of Disaggregation of Revenue from Contracts with Customers Accounted Under ASC 606

14. Revenue from Contracts with Customers Accounted for in Accordance with ASC 606

The following tables illustrate the disaggregation of revenue from contracts accounted for under ASC 606 with customers according to service type and client type by reportable operating segment.

Revenue by Service Type

	Years Ended December 31,
	2020						2019
(Dollars in millions)	Federal Education Loans		Business Processing		Total Revenue		Federal Education Loans		Business Processing		Total Revenue
Federal Education Loan asset recovery services	$	84	$	—	$	84	$	133	$	—	$	133
Government services		—		191		191		—		154		154
Healthcare services		—		113		113		—		104		104
Total	$	84	$	304	$	388	$	133	$	258	$	391

Revenue by Client Type

	Years Ended December 31,
	2020						2019
(Dollars in millions)	Federal Education Loans		Business Processing		Total Revenue		Federal Education Loans		Business Processing		Total Revenue
Federal government	$	44	$	18	$	62	$	74	$	17	$	91
Guarantor agencies		38		—		38		52		—		52
Other institutions		2		—		2		7		—		7
State and local government		—		122		122		—		83		83
Tolling authorities		—		51		51		—		54		54
Hospitals and other healthcare providers		—		113		113		—		104		104
Total	$	84	$	304	$	388	$	133	$	258	$	391

Allowance for Loan Losses - Loan Type (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable Recorded Investment Past Due [Line Items]
Total loans, gross		$ 88,013	$ 96,014
FFELP Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total loans, gross	$ 58,572	64,094	$ 71,730
Change	(5,522)
FFELP Loans [Member] \| Stafford Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total loans, gross	17,686	19,093
Change	(1,407)
FFELP Loans [Member] \| Consolidation Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total loans, gross	35,968	39,706
Change	(3,738)
FFELP Loans [Member] \| Rehab Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total loans, gross	4,918	$ 5,295
Change	$ (377)

Borrowings - Financing VIEs (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Securities Financing Transaction [Line Items]
Short-term borrowings	$ 6,613	$ 8,483
Long-term borrowings	77,332	81,715
Total	83,945	90,198
Loans	79,363	86,820
Total assets	87,412	94,903
Total Before Hedge Accounting Adjustments [Member]
Securities Financing Transaction [Line Items]
Short-term borrowings	6,609	8,479
Long-term borrowings	76,781	81,756
Total	83,390	90,235
Hedge Accounting Adjustments [Member]
Securities Financing Transaction [Line Items]
Short-term borrowings	4	4
Long-term borrowings	551	(41)
Total	555	(37)
Assets and Liabilities of Consolidated Variable Interest Entities [Member]
Securities Financing Transaction [Line Items]
Short-term borrowings	5,595	7,089
Long-term borrowings	68,900	72,856
Total	74,495	79,945
Loans	76,726	83,864
Cash	2,322	2,506
Other assets, Net	1,420	1,089
Total assets	80,468	87,459
Assets and Liabilities of Consolidated Variable Interest Entities [Member] \| FFELP Loan Securitizations [Member]
Securities Financing Transaction [Line Items]
Short-term borrowings		72
Long-term borrowings	54,697	59,735
Total	54,697	59,807
Loans	55,535	60,834
Cash	1,606	1,833
Other assets, Net	1,438	1,400
Total assets	58,579	64,067
Assets and Liabilities of Consolidated Variable Interest Entities [Member] \| Private Education Loan Securitizations [Member]
Securities Financing Transaction [Line Items]
Short-term borrowings	960	2,120
Long-term borrowings	13,891	11,430
Total	14,851	13,550
Loans	15,823	15,412
Cash	606	509
Other assets, Net	187	152
Total assets	16,616	16,073
Assets and Liabilities of Consolidated Variable Interest Entities [Member] \| FFELP Loan ABCP Facilities [Member]
Securities Financing Transaction [Line Items]
Short-term borrowings	2,053	2,783
Long-term borrowings	479	617
Total	2,532	3,400
Loans	2,533	3,421
Cash	36	63
Other assets, Net	76	102
Total assets	2,645	3,586
Assets and Liabilities of Consolidated Variable Interest Entities [Member] \| Private Education Loan ABCP Facilities [Member]
Securities Financing Transaction [Line Items]
Short-term borrowings	2,582	2,114
Long-term borrowings		1,513
Total	2,582	3,627
Loans	2,835	4,197
Cash	74	101
Other assets, Net	27	28
Total assets	2,936	4,326
Assets and Liabilities of Consolidated Variable Interest Entities [Member] \| Total Before Hedge Accounting Adjustments [Member]
Securities Financing Transaction [Line Items]
Short-term borrowings	5,595	7,089
Long-term borrowings	69,067	73,295
Total	74,662	80,384
Loans	76,726	83,864
Cash	2,322	2,506
Other assets, Net	1,728	1,682
Total assets	80,776	88,052
Assets and Liabilities of Consolidated Variable Interest Entities [Member] \| Hedge Accounting Adjustments [Member]
Securities Financing Transaction [Line Items]
Long-term borrowings	(167)	(439)
Total	(167)	(439)
Other assets, Net	(308)	(593)
Total assets	$ (308)	$ (593)

Significant Accounting Policies

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Significant Accounting Policies

2. Significant Accounting Policies

Use of Estimates

Consolidation

2. Significant Accounting Policies (Continued)

Fair Value Measurement

We use estimates of fair value in applying various accounting standards for our financial statements. Fair value measurements are used in one of four ways:

•

In the balance sheet with changes in fair value recorded in the statement of income;

•

In the balance sheet with changes in fair value recorded in the accumulated other comprehensive income section of the statement of changes in stockholders’ equity;

•

In the balance sheet for instruments carried at lower of cost or fair value with impairment charges recorded in the statement of income; and

•

In the notes to the financial statements.

•

Loans

2. Significant Accounting Policies (Continued)

Allowance for Loan Losses

Related to this new standard:

•

Charge-offs include the discount or premium related to such defaulted loan.

•

2. Significant Accounting Policies (Continued)

(Dollars in millions)	FFELP Loans		Private Education Loans			Total
Allowance as of December 31, 2019 (prior to CECL)	$	64	$	1,048		$	1,112
Transition adjustments made under CECL on January 1, 2020:
Current expected credit losses on non-PCD portfolio⁽¹⁾		260		542			802
Current expected credit losses on PCD portfolio⁽²⁾		—		43			43
Reclassification of the expected future recoveries on charged-off loans⁽³⁾		—		(588	)		(588	)
Net increase to allowance for loan losses under CECL		260		(3	)		257
Allowance as of January 1, 2020 after CECL	$	324	$	1,045		$	1,369

⁽¹⁾	Recorded net of tax through retained earnings. Resulted in a $620 million reduction to equity.

⁽²⁾	Recorded as an increase in basis of the loans. No impact to equity.

⁽³⁾	Reclassification of the expected future recoveries on charged-off loans (previously referred to as the receivable for partially charged-off loans) from the Private Education Loan balance to the allowance for loan losses. No impact to equity.

2. Significant Accounting Policies (Continued)

Allowance for Loan Losses Prior to the Adoption of CECL

Private Education Loans

2. Significant Accounting Policies (Continued)

FFELP Loans

Investments

Other investments are primarily receivables for cash collateral posted to derivative counterparties.

Cash and Cash Equivalents

Restricted Cash and Investments

Goodwill and Acquired Intangible Assets

2. Significant Accounting Policies (Continued)

Irrespective of whether a securitization receives sale or on-balance sheet treatment, our continuing involvement with our securitization trusts is generally limited to:

•	Owning equity certificates or other certificates of certain trusts and, in certain cases, securities retained for the purpose of complying with risk retention requirements under securities laws.

•	Lending to certain trusts, under a revolving credit, amounts necessary to cover temporary cash flow needs of the trust. These amounts are repaid to us on subordinated basis with interest at a market rate.

•	The servicing of the education loan assets within the securitization trusts, on both a pre- and post-default basis.

•	Our acting as administrator for the securitization transactions we sponsored, which includes remarketing certain bonds at future dates.

•	Our responsibilities relative to representation and warranty violations.

•	Temporarily advancing to the trust certain borrower benefits afforded the borrowers of education loans that have been securitized. These advances subsequently are returned to us in the next quarter.

•	Certain back-to-back derivatives entered into by us contemporaneously with the execution of derivatives by certain Private Education Loan securitization trusts.

•	The option held by us to buy certain delinquent loans from certain Private Education Loan securitization trusts.

•	The option to exercise the clean-up call and purchase the education loans from the trust when the asset balance is 10% or less of the original loan balance.

•	The option, on some trusts, to purchase education loans aggregating up to 10% of the trust’s initial pool balance.

•	The option (in certain trusts) to call rate reset notes in instances where the remarketing process has failed.

2. Significant Accounting Policies (Continued)

Education Loan Interest Income

Interest Expense

Servicing Revenue

Asset Recovery and Business Processing Revenue

2. Significant Accounting Policies (Continued)

Transfer of Financial Assets and Extinguishments of Liabilities

We recognize the results of a transfer of loans and the extinguishment of debt based upon the settlement date of the transaction.

Derivative Accounting

2. Significant Accounting Policies (Continued)

Fair Value Hedges

Cash Flow Hedges

Trading Activities

Accounting for Stock-Based Compensation

2. Significant Accounting Policies (Continued)

Restructuring and Other Reorganization Expenses

Other reorganization expenses include certain internal costs and third-party costs incurred in connection with our cost reduction initiatives.

Income Taxes

Earnings (Loss) per Common Share

2. Significant Accounting Policies (Continued)

Recently Issued Accounting Pronouncements

Effective in 2020

Allowance for Loan Losses

Goodwill

Rate Reform

Segment Reporting (Tables)

12 Months Ended

Dec. 31, 2020

Segment Results and Reconciliations to GAAP

	Year Ended December 31, 2020
													Adjustments
(Dollars in millions)	Federal Education Loans		Consumer Lending		Business Processing		Other			Total Core Earnings			Reclassi- fications			Additions/ (Subtractions)			Total Adjustments⁽¹⁾			Total GAAP
Interest income:
Education loans	$	1,813	$	1,445	$	—	$	—		$	3,258		$	79		$	(55	)	$	24		$	3,282
Other loans		—		—		—		—			—			—			—			—			—
Cash and investments		7		3		—		6			16			—			—			—			16
Total interest income		1,820		1,448		—		6			3,274			79			(55	)		24			3,298
Total interest expense		1,194		699		—		120			2,013			39			(6	)		33			2,046
Net interest income (loss)		626		749		—		(114	)		1,261			40			(49	)		(9	)		1,252
Less: provisions for loan losses		13		142		—		—			155			—			—			—			155
Net interest income (loss) after provisions for loan losses		613		607		—		(114	)		1,106			40			(49	)		(9	)		1,097
Other income (loss):
Servicing revenue		208		6		—		—			214			—			—			—			214
Asset recovery and business processing revenue		154		—		304		—			458			—			—			—			458
Other income (loss)		9		—		—		11			20			(40	)		(216	)		(256	)		(236	)
Losses on debt repurchases		—		—		—		(6	)		(6	)		—			—			—			(6	)
Total other income (loss)		371		6		304		5			686			(40	)		(216	)		(256	)		430
Expenses:
Direct operating expenses		287		146		254		—			687			—			—			—			687
Unallocated shared services expenses		—		—		—		277			277			—			—			—			277
Operating expenses		287		146		254		277			964			—			—			—			964
Goodwill and acquired intangible asset impairment and amortization		—		—		—		—			—			—			22			22			22
Restructuring/other reorganization expenses		—		—		—		9			9			—			—			—			9
Total expenses		287		146		254		286			973			—			22			22			995
Income (loss) before income tax expense (benefit)		697		467		50		(395	)		819			—			(287	)		(287	)		532
Income tax expense (benefit)⁽²⁾		160		107		11		(90	)		188			—			(68	)		(68	)		120
Net income (loss)	$	537	$	360	$	39	$	(305	)	$	631		$	—		$	(219	)	$	(219	)	$	412

⁽¹⁾	Core Earnings adjustments to GAAP:

	Year Ended December 31, 2020
(Dollars in millions)	Net Impact of Derivative Accounting			Net Impact of Acquired Intangibles			Total
Net interest income (loss) after provisions for loan losses	$	(9	)	$	—		$	(9	)
Total other income (loss)		(256	)		—			(256	)
Goodwill and acquired intangible asset impairment and amortization		—			22			22
Total Core Earnings adjustments to GAAP	$	(265	)	$	(22	)		(287	)
Income tax expense (benefit)								(68	)
Net income (loss)							$	(219	)

⁽²⁾	Income taxes are based on a percentage of net income before tax for the individual reportable segment.

	Year Ended December 31, 2019
												Adjustments
(Dollars in millions)	Federal Education Loans		Consumer Lending		Business Processing		Other			Total Core Earnings		Reclassi- fications			Additions/ (Subtractions)			Total Adjustments⁽¹⁾			Total GAAP
Interest income:
Education loans	$	2,907	$	1,731	$	—	$	—		$	4,638	$	8		$	(68	)	$	(60	)	$	4,578
Other loans		1		1		—		—			2		—			—			—			2
Cash and investments		50		16		—		27			93		—			—			—			93
Total interest income		2,958		1,748		—		27			4,733		8			(68	)		(60	)		4,673
Total interest expense		2,376		980		—		161			3,517		6			(35	)		(29	)		3,488
Net interest income (loss)		582		768		—		(134	)		1,216		2			(33	)		(31	)		1,185
Less: provisions for loan losses		30		228		—		—			258		—			—			—			258
Net interest income (loss) after provisions for loan losses		552		540		—		(134	)		958		2			(33	)		(31	)		927
Other income (loss):
Servicing revenue		229		11		—		—			240		—			—			—			240
Asset recovery and business processing revenue		230		—		258		—			488		—			—			—			488
Other income (loss)		28		1		—		14			43		(41	)		65			24			67
Gains on sales of loans		—		16		—		—			16		—			—			—			16
Gains on debt repurchases		—		—		—		33			33		39			(27	)		12			45
Total other income (loss)		487		28		258		47			820		(2	)		38			36			856
Expenses:
Direct operating expenses		359		156		215		—			730		—			—			—			730
Unallocated shared services expenses		—		—		—		254			254		—			—			—			254
Operating expenses		359		156		215		254			984		—			—			—			984
Goodwill and acquired intangible asset impairment and amortization		—		—		—		—			—		—			30			30			30
Restructuring/other reorganization expenses		—		—		—		6			6		—			—			—			6
Total expenses		359		156		215		260			990		—			30			30			1,020
Income (loss) before income tax expense (benefit)		680		412		43		(347	)		788		—			(25	)		(25	)		763
Income tax expense (benefit)⁽²⁾		155		96		10		(80	)		181		—			(15	)		(15	)		166
Net income (loss)	$	525	$	316	$	33	$	(267	)	$	607	$	—		$	(10	)	$	(10	)	$	597

⁽¹⁾	Core Earnings adjustments to GAAP:

	Year Ended December 31, 2019
(Dollars in millions)	Net Impact of Derivative Accounting			Net Impact of Acquired Intangibles			Total
Net interest income after provisions for loan losses	$	(31	)	$	—		$	(31	)
Total other income (loss)		36			—			36
Goodwill and acquired intangible asset impairment and amortization		—			30			30
Total Core Earnings adjustments to GAAP	$	5		$	(30	)		(25	)
Income tax expense (benefit)								(15	)
Net income (loss)							$	(10	)

⁽²⁾	Income taxes are based on a percentage of net income before tax for the individual reportable segment.

	Year Ended December 31, 2018
												Adjustments
(Dollars in millions)	Federal Education Loans		Consumer Lending		Business Processing		Other			Total Core Earnings		Reclassi- fications			Additions/ (Subtractions)			Total Adjustments⁽¹⁾			Total GAAP
Interest income:
Education loans	$	3,080	$	1,778	$	—	$	—		$	4,858	$	17		$	(70	)	$	(53	)	$	4,805
Other loans		4		2		—		—			6		—			—			—			6
Cash and investments		46		13		—		38			97		—			—			—			97
Total interest income		3,130		1,793		—		38			4,961		17			(70	)		(53	)		4,908
Total interest expense		2,467		1,013		—		192			3,672		8			(12	)		(4	)		3,668
Net interest income (loss)		663		780		—		(154	)		1,289		9			(58	)		(49	)		1,240
Less: provisions for loan losses		70		300		—		—			370		—			—			—			370
Net interest income (loss) after provisions for loan losses		593		480		—		(154	)		919		9			(58	)		(49	)		870
Other income (loss):
Servicing revenue		262		12		—		—			274		—			—			—			274
Asset recovery and business processing revenue		163		—		267		—			430		—			—			—			430
Other income (loss)		24		—		—		6			30		(22	)		(29	)		(51	)		(21	)
Gains on debt repurchases		—		—		—		9			9		13			(3	)		10			19
Total other income (loss)		449		12		267		15			743		(9	)		(32	)		(41	)		702
Expenses:
Direct operating expenses		298		169		229		—			696		—			—			—			696
Unallocated shared services expenses		—		—		—		288			288		—			—			—			288
Operating expenses		298		169		229		288			984		—			—			—			984
Goodwill and acquired intangible asset impairment and amortization		—		—		—		—			—		—			47			47			47
Restructuring/other reorganization expenses		—		—		—		13			13		—			—			—			13
Total expenses		298		169		229		301			997		—			47			47			1,044
Income (loss) before income tax expense (benefit)		744		323		38		(440	)		665		—			(137	)		(137	)		528
Income tax expense (benefit)⁽²⁾		164		71		8		(97	)		146		—			(13	)		(13	)		133
Net income (loss)	$	580	$	252	$	30	$	(343	)	$	519	$	—		$	(124	)	$	(124	)	$	395

⁽¹⁾	Core Earnings adjustments to GAAP:

	Year Ended December 31, 2018
(Dollars in millions)	Net Impact of Derivative Accounting			Net Impact of Acquired Intangibles			Total
Net interest income after provisions for loan losses	$	(49	)	$	—		$	(49	)
Total other income (loss)		(41	)		—			(41	)
Goodwill and acquired intangible asset impairment and amortization		—			47			47
Total Core Earnings adjustments to GAAP	$	(90	)	$	(47	)		(137	)
Income tax expense (benefit)								(13	)
Net income (loss)							$	(124	)

⁽²⁾	Income taxes are based on a percentage of net income before tax for the individual reportable segment with the impact of the DTA Remeasurement Loss included in the Other segment.

Core Earnings Adjustments to GAAP

Summary of Core Earnings Adjustments to GAAP

	Years Ended December 31,
(Dollars in millions)	2020			2019			2018
Core Earnings net income	$	631		$	607		$	519
Core Earnings adjustments to GAAP:
Net impact of derivative accounting⁽¹⁾		(265	)		5			(90	)
Net impact of goodwill and acquired intangible assets⁽²⁾		(22	)		(30	)		(47	)
Net income tax effect⁽³⁾		68			15			13
Total Core Earnings adjustments to GAAP		(219	)		(10	)		(124	)
GAAP net income	$	412		$	597		$	395

⁽¹⁾

⁽²⁾

Goodwill and acquired intangible assets: Our Core Earnings exclude goodwill and intangible asset impairment and amortization of acquired intangible assets.

⁽³⁾

Net tax effect: Such tax effect is based upon our Core Earnings effective tax rate for the year.

Federal Education Loans [Member]

Asset Information for Loans Segment

The following table includes asset information for our Federal Education Loans segment.

	December 31,
(Dollars in millions)	2020		2019
FFELP Loans, net	$	58,284	$	64,575
Cash and investments⁽¹⁾		1,685		2,043
Other		2,241		2,202
Total assets	$	62,210	$	68,820

⁽¹⁾

Includes restricted cash and investments.

Consumer Lending [Member]

Asset Information for Loans Segment

The following table includes asset information for our Consumer Lending segment.

	December 31,
(Dollars in millions)	2020		2019
Private Education Loans, net	$	21,079	$	22,245
Cash and investments⁽¹⁾		828		927
Other		964		931
Total assets	$	22,871	$	24,103

⁽¹⁾

Includes restricted cash and investments.

Derivative Financial Instruments - Carrying Value and Related Fair Value Hedging Adjustments of Liabilities (Detail) - Designated as Hedging Instrument [Member] - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Short-term borrowings [Member]
Derivatives Fair Value [Line Items]
Carrying Value	$ 631	$ 1,001
Hedge Basis Adjustments	4	4
Long-term borrowings [Member]
Derivatives Fair Value [Line Items]
Carrying Value	11,017	11,488
Hedge Basis Adjustments	$ 541	$ (58)

Borrowings - Summary of Activity Related to Senior Unsecured Debt Repurchases (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt principal repurchased	$ 768	$ 1,184	$ 2,809
Gains (losses) on debt repurchases	$ (6)	$ 45	$ 19

Derivative Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2020

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Schedule of Credit Exposure Related to Our Derivative Counterparties

The table below highlights credit exposure related to our derivative counterparties at December 31, 2020.

(Dollars in millions)	Corporate Contracts			Securitization Trust Contracts
Exposure, net of collateral	$	13		$	28
Percent of exposure to counterparties with credit ratings below S&P AA- or Moody’s Aa3		100	%		—	%
Percent of exposure to counterparties with credit ratings below S&P A- or Moody’s A3		—	%		—	%

Impact of Derivatives on Balance Sheet

The following tables summarize the fair values and notional amounts of all derivative instruments and their impact on net income and other comprehensive income.

Impact of Derivatives on Balance Sheet

		Cash Flow				Fair Value⁽⁴⁾						Trading						Total
(Dollars in millions)	Hedged Risk Exposure	Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2020			Dec. 31, 2019			Dec. 31, 2020			Dec. 31, 2019			Dec. 31, 2020			Dec. 31, 2019
Fair Values⁽¹⁾
Derivative Assets:
Interest rate swaps	Interest rate	$	—	$	—	$	323		$	226		$	6		$	4		$	329		$	230
Cross-currency interest rate swaps	Foreign currency and interest rate		—		—		28			—			—			—			28			—
Total derivative assets⁽²⁾			—		—		351			226			6			4			357			230
Derivative Liabilities:
Interest rate swaps	Interest rate		—		—		—			—			(14	)		(20	)		(14	)		(20	)
Floor Income Contracts	Interest rate		—		—		—			—			(197	)		(68	)		(197	)		(68	)
Cross-currency interest rate swaps	Foreign currency and interest rate		—		—		(322	)		(575	)		—			—			(322	)		(575	)
Other⁽³⁾	Interest rate		—		—		—			—			—			(1	)		—			(1	)
Total derivative liabilities⁽²⁾			—		—		(322	)		(575	)		(211	)		(89	)		(533	)		(664	)
Net total derivatives		$	—	$	—	$	29		$	(349	)	$	(205	)	$	(85	)	$	(176	)	$	(434	)

⁽¹⁾

⁽²⁾	The following table reconciles gross positions without the impact of master netting agreements to the balance sheet classification:

	Other Assets						Other Liabilities
(Dollar in millions)	December 31, 2020			December 31, 2019			December 31, 2020			December 31, 2019
Gross position	$	357		$	230		$	(533	)	$	(664	)
Impact of master netting agreements		(50	)		(18	)		50			18
Derivative values with impact of master netting agreements (as carried on balance sheet)		307			212			(483	)		(646	)
Cash collateral (held) pledged		(336	)		(337	)		234			155
Net position	$	(29	)	$	(125	)	$	(249	)	$	(491	)

⁽³⁾	^{“Other” includes derivatives related to our Total Return Swap Facility.}

⁽⁴⁾	^{The following table shows the carrying value of liabilities in fair value hedges and the related fair value hedging adjustments to these liabilities:}

	As of December 31, 2020				As of December 31, 2019
(Dollar in millions)	Carrying Value		Hedge Basis Adjustments		Carrying Value		Hedge Basis Adjustments
Short-term borrowings	$	631	$	4	$	1,001	$	4
Long-term borrowings	$	11,017	$	541	$	11,488	$	(58	)

Gross Positions with Impact of Master Netting Agreements

The following table reconciles gross positions without the impact of master netting agreements to the balance sheet classification:

	Other Assets						Other Liabilities
(Dollar in millions)	December 31, 2020			December 31, 2019			December 31, 2020			December 31, 2019
Gross position	$	357		$	230		$	(533	)	$	(664	)
Impact of master netting agreements		(50	)		(18	)		50			18
Derivative values with impact of master netting agreements (as carried on balance sheet)		307			212			(483	)		(646	)
Cash collateral (held) pledged		(336	)		(337	)		234			155
Net position	$	(29	)	$	(125	)	$	(249	)	$	(491	)

⁽³⁾	^{“Other” includes derivatives related to our Total Return Swap Facility.}

⁽⁴⁾	^{The following table shows the carrying value of liabilities in fair value hedges and the related fair value hedging adjustments to these liabilities:}

Carrying Value and Related Fair Value Hedging Adjustments of Liabilities

The following table shows the carrying value of liabilities in fair value hedges and the related fair value hedging adjustments to these liabilities:

	As of December 31, 2020				As of December 31, 2019
(Dollar in millions)	Carrying Value		Hedge Basis Adjustments		Carrying Value		Hedge Basis Adjustments
Short-term borrowings	$	631	$	4	$	1,001	$	4
Long-term borrowings	$	11,017	$	541	$	11,488	$	(58	)

Derivative Notional Values

	Cash Flow				Fair Value				Trading				Total
(Dollars in billions)	Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2020		Dec. 31, 2019
Notional Values:
Interest rate swaps	$	16.7	$	19.1	$	7.5	$	8.6	$	26.8	$	51.5	$	51.0	$	79.2
Floor Income Contracts		—		—		—		—		17.0		21.2		17.0		21.2
Cross-currency interest rate swaps		—		—		3.7		4.0		—		—		3.7		4.0
Total derivatives	$	16.7	$	19.1	$	11.2	$	12.6	$	43.8	$	72.7	$	71.7	$	104.4

Mark-to-Market Impact of Derivatives on Statements of Income

	Total Gains (Losses)
	Years Ended December 31,
(Dollars in millions)	2020			2019			2018
Fair Value Hedges⁽²⁾:
Interest Rate Swaps
Gains (losses) recognized in net income on derivatives	$	301		$	281		$	(137	)
Gains (losses) recognized in net income on hedged items		(327	)		(299	)		162
Net fair value hedge ineffectiveness gains (losses)		(26	)		(18	)		25
Cross currency interest rate swaps
Gains (losses) recognized in net income on derivatives		281			57			(311	)
Gains (losses) recognized in net income on hedged items		(272	)		(18	)		210
Net fair value hedge ineffectiveness gains (losses)		9			39			(101	)
Total fair value hedges⁽¹⁾⁽²⁾		(17	)		21			(76	)
Cash Flow Hedges:
Total cash flow hedges⁽²⁾		—			—			—
Trading
Interest rate swaps		(47	)		44			22
Floor income contracts		(209	)		(22	)		15
Cross currency interest rate swaps		—			(2	)		(3	)
Other		—			2			4
Total trading derivatives⁽³⁾		(256	)		22			38
Mark-to-market gains (losses) recognized	$	(273	)	$	43		$	(38	)

⁽¹⁾	Recorded in interest expense in the consolidated statements of income for 2020 and 2019 with the adoption of ASU No. 2017-12. Recorded in “gains (losses) on derivatives and hedging activities, net” in the consolidated statements of income for 2018.

⁽²⁾	The accrued interest income (expense) on fair value hedges and cash flow hedges is recorded in interest expense and is excluded from this table.

⁽³⁾	Recorded in “gains (losses) on derivative and hedging activities, net” in the consolidated statements of income.

Impact of Derivatives on Other Comprehensive Income (Equity)

	Years Ended December 31,
(Dollars in millions)	2020			2019			2018
Total gains (losses) on cash flow hedges	$	(233	)	$	(165	)	$	50
Reclassification adjustments for derivative (gains) losses included in net income (interest expense)⁽¹⁾		50			(39	)		(11	)
Net changes in cash flow hedges, net of tax	$	(183	)	$	(204	)	$	39

⁽¹⁾

Includes net settlement income/expense.

Collateral Held and Pledged

The following table details collateral held and pledged related to derivative exposure between us and our derivative counterparties.

(Dollars in millions)	December 31, 2020		December 31, 2019
Collateral held:
Cash (obligation to return cash collateral is recorded in short-term borrowings)	$	336	$	337
Securities at fair value — corporate derivatives (not recorded in financial statements)⁽¹⁾		—		—
Securities at fair value — on-balance sheet securitization derivatives (not recorded in financial statements)⁽²⁾		78		69
Total collateral held	$	414	$	406
Derivative asset at fair value including accrued interest	$	351	$	282
Collateral pledged to others:
Cash (right to receive return of cash collateral is recorded in investments)	$	234	$	155
Total collateral pledged	$	234	$	155
Derivative liability at fair value including accrued interest and premium receivable	$	504	$	658

⁽¹⁾	The Company has the ability to sell or re-pledge securities it holds as collateral.

⁽²⁾	The trusts do not have the ability to sell or re-pledge securities they hold as collateral.

Allowance for Loan Losses

12 Months Ended

Dec. 31, 2020

Receivables [Abstract]

Allowance for Loan Losses

4. Allowance for Loan Losses

See “Note 2 – Significant Accounting Policies” for discussion of the adoption of CECL on January 1, 2020.

Allowance for Loan Losses Metrics

	Year Ended December 31, 2020
(Dollars in millions)	FFELP Loans			Private Education Loans			Total
Allowance at beginning of period (after transition adjustment to CECL on January 1, 2020)	$	324		$	1,045		$	1,369
Total provision		13			142			155
Charge-offs:
Net adjustment resulting from the change in the charge-off rate⁽¹⁾		—			(23	)		(23	)
Net charge-offs remaining⁽²⁾		(49	)		(184	)		(233	)
Total charge-offs⁽²⁾		(49	)		(207	)		(256	)
Decrease in expected future recoveries on charged-off loans⁽³⁾		—			109			109
Allowance at end of period		288			1,089			1,377
Plus: expected future recoveries on charged-off loans⁽³⁾		—			479			479
Allowance at end of period excluding expected future recoveries on charged-off loans⁽⁴⁾	$	288		$	1,568		$	1,856
Net charge-offs as a percentage of average loans in repayment, excluding the net adjustment resulting from the change in the charge-off rate⁽¹⁾		.10	%		.88	%
Net adjustment resulting from the change in charge-off rate as a percentage of average loans in repayment⁽¹⁾		—	%		.11	%
Allowance coverage of charge-offs⁽⁴⁾		5.9			7.6
Allowance as a percentage of the ending total loan balance⁽⁴⁾		.5	%		7.1	%
Allowance as a percentage of the ending loans in repayment⁽⁴⁾		.6	%		7.5	%
Ending total loans	$	58,572		$	22,168
Average loans in repayment	$	48,130		$	20,790
Ending loans in repayment	$	48,057		$	20,841

⁽¹⁾	In 2020, the portion of the loan amount charged off at default on Private Education Loans increased from 81% to 81.4%. This charge resulted in a $23 million reduction to the balance of the receivable for partially charged-off loan balance.

⁽²⁾

⁽³⁾

	Year Ended December 31,
(Dollars in millions)	2020
Beginning of period expected recoveries	$	588
Expected future recoveries of current period defaults		32
Recoveries		(107	)
Charge-offs		(34	)
End of period expected recoveries	$	479
Change in balance during period	$	(109	)

⁽⁴⁾	The allowance used for these metrics excludes the expected future recoveries on charged-off loans to better reflect the current expected credit losses remaining in the portfolio.

4. Allowance for Loan Losses (Continued)

	Year Ended December 31, 2019
(Dollars in millions)	FFELP Loans			Private Education Loans			Other Loans			Total
Beginning balance	$	76		$	1,201		$	9		$	1,286
Total provision		30			226			1			258
Net adjustment resulting from the change in the charge-off rate⁽¹⁾		—			(21	)		—			(21	)
Net charge-offs remaining⁽²⁾		(42	)		(364	)		(2	)		(408	)
Total net charge-offs		(42	)		(385	)		(2	)		(429	)
Reclassification of interest reserve⁽³⁾		—			7			—			7
Loan sales		—			(1	)		(8	)		(9	)
Ending balance	$	64		$	1,048		$	—		$	1,112
Allowance Ending Balance:
Individually evaluated for impairment — TDR	$	—		$	941		$	—		$	941
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans		64			107			—			171
Purchased Non-Credit Impaired Loans acquired at a discount⁽⁴⁾		—			—			—			—
Purchased Credit Impaired Loans⁽⁴⁾		—			—			—			—
Ending total allowance	$	64		$	1,048		$	—		$	1,112
Loans Ending Balance:
Individually evaluated for impairment — TDR	$	—		$	9,617		$	—		$	9,617
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans		61,589			12,286			9			73,884
Purchased Non-Credit Impaired Loans acquired at a discount⁽⁴⁾		2,505			1,806			—			4,311
Purchased Credit Impaired Loans⁽⁴⁾		—			201			—			201
Ending total loans⁽⁵⁾	$	64,094		$	23,910		$	9		$	88,013
Net charge-offs as a percentage of average loans in repayment, excluding the net adjustment resulting from the change in the charge-off rate⁽¹⁾		.07	%		1.67	%		—	%
Net adjustment resulting from the change in charge-off rate as a percentage of average loans in repayment⁽¹⁾		—	%		.10	%		—	%
Allowance coverage of charge-offs		1.5			2.7			—
Allowance as a percentage of the ending total loan balance		.10	%		4.38	%		—	%
Allowance as a percentage of the ending loans in repayment		.12	%		4.74	%		—	%
Ending total loans⁽⁵⁾	$	64,094		$	23,910		$	9
Average loans in repayment	$	55,978		$	21,859		$	29
Ending loans in repayment	$	53,538		$	22,089		$	9

⁽¹⁾

₍₂₎

⁽³⁾

⁽⁴⁾

⁽⁵⁾

Ending total loans for Private Education Loans includes the receivable for partially charged-off loans.

4. Allowance for Loan Losses (Continued)

	Year Ended December 31, 2018
(Dollars in millions)	FFELP Loans			Private Education Loans			Other Loans			Total
Allowance for Loan Losses
Beginning balance	$	60		$	1,297		$	10		$	1,367
Total provision		70			299			1			370
Net adjustment resulting from the change in the charge- off rate⁽¹⁾		—			(32	)		—			(32	)
Net charge-offs remaining⁽²⁾		(54	)		(371	)		(2	)		(427	)
Total net charge-offs		(54	)		(403	)		(2	)		(459	)
Reclassification of interest reserve⁽³⁾		—			8			—			8
Ending balance	$	76		$	1,201		$	9		$	1,286
Allowance Ending Balance:
Individually evaluated for impairment — TDR	$	—		$	1,100		$	8		$	1,108
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans		76			101			1			178
Purchased Non-Credit Impaired Loans acquired at a discount⁽⁴⁾		—			—			—			—
Purchased Credit Impaired Loans⁽⁴⁾		—			—			—			—
Ending total allowance	$	76		$	1,201		$	9		$	1,286
Loans Ending Balance:
Individually evaluated for impairment — TDR	$	—		$	10,336		$	28		$	10,364
Collectively evaluated for impairment:
Excluding Purchased Non-Credit Impaired Loans acquired at a discount and Purchased Credit Impaired Loans		68,880			11,464			51			80,395
Purchased Non-Credit Impaired Loans acquired at a discount⁽⁴⁾		2,850			2,180			—			5,030
Purchased Credit Impaired Loans⁽⁴⁾		—			225			—			225
Ending total loans⁽⁵⁾	$	71,730		$	24,205		$	79		$	96,014
Net charge-offs as a percentage of average loans in repayment, excluding the net adjustment resulting from the change in the charge-off rate⁽¹⁾		.09	%		1.66	%		—	%
Net adjustment resulting from the change in charge-off rate as a percentage of average loans in repayment⁽¹⁾		—	%		.14	%		—	%
Allowance coverage of charge-offs		1.4			3.0			—
Allowance as a percentage of the ending total loan balance		.11	%		4.96	%		11.52	%
Allowance as a percentage of the ending loans in repayment		.13	%		5.45	%		11.52	%
Ending total loans⁽⁵⁾	$	71,730		$	24,205		$	79
Average loans in repayment	$	62,927		$	22,312		$	75
Ending loans in repayment	$	59,551		$	22,037		$	79

⁽¹⁾

⁽²⁾

⁽³⁾

⁽⁴⁾

The Purchased Credit Impaired Loans’ losses are not provided for by the allowance for loan losses in the above table as these loans are separately reserved for, if needed. No allowance for loan losses has been established for these loans as of December 31, 2018. The losses of the Purchased Non-Credit Impaired Loans acquired at a discount are not provided for by the allowance for loan losses in the above table as the remaining purchased discount associated with the FFELP and Private Education Loans of $37 million and $326 million respectively, as of December 31, 2018 is greater than the incurred losses and as a result no allowance for loan losses has been established for these loans as of December 31, 2018.

⁽⁵⁾

Ending total loans for Private Education Loans includes the receivable for partially charged-off loans.

4. Allowance for Loan Losses (Continued)

Troubled Debt Restructurings (TDRs)

We sometimes modify the terms of loans for customers experiencing financial difficulty. Certain Private Education Loans for which we have granted either a forbearance of greater than three months, an interest rate reduction or an extended repayment plan are classified as TDRs. Approximately 72% and 69% of the loans granted forbearance have qualified as a TDR loan at December 31, 2020 and 2019, respectively. The unpaid principal balance of TDR loans that were in an interest rate reduction program as of December 31, 2020 and 2019 was $948 million and $1.7 billion, respectively.

	Years Ended December 31,
(Dollars in millions)	2020		2019		2018
Modified loans⁽¹⁾	$	264	$	475	$	596
Charge-offs⁽²⁾	$	157	$	324	$	343
Payment default	$	47	$	109	$	142

⁽¹⁾ Represents period ending balance of loans that have been modified during the period and resulted in a TDR.

⁽²⁾ Represents loans that charged off that were classified as TDRs.

4. Allowance for Loan Losses (Continued)

Key Credit Quality Indicators

We assess and determine the collectability of our education loan portfolios by evaluating certain risk characteristics we refer to as key credit quality indicators. Key credit quality indicators are incorporated into the allowance for loan losses calculation.

FFELP Loans

FFELP Loans are substantially insured and guaranteed as to their principal and accrued interest in the event of default. The key credit quality indicators are loan status and loan type.

	FFELP Loan Delinquencies
	December 31, 2020						December 31, 2019
(Dollars in millions)	Balance			%			Balance			%
Loans in-school/grace/deferment⁽¹⁾	$	2,791					$	3,114
Loans in forbearance⁽²⁾		7,725						7,442
Loans in repayment and percentage of each status:
Loans current		43,623			90.8	%		47,255			88.3	%
Loans delinquent 31-60 days⁽³⁾		1,374			2.9			2,094			3.9
Loans delinquent 61-90 days⁽³⁾		836			1.7			1,082			2.0
Loans delinquent greater than 90 days⁽³⁾		2,223			4.6			3,107			5.8
Total FFELP Loans in repayment		48,056			100	%		53,538			100	%
Total FFELP Loans, gross		58,572						64,094
FFELP Loan unamortized premium⁽⁴⁾		—						545
Total FFELP Loans		58,572						64,639
FFELP Loan allowance for losses		(288	)					(64	)
FFELP Loans, net	$	58,284					$	64,575
Percentage of FFELP Loans in repayment					82.0	%					83.5	%
Delinquencies as a percentage of FFELP Loans in repayment					9.2	%					11.7	%
FFELP Loans in forbearance as a percentage of loans in repayment and forbearance					13.8	%					12.2	%

⁽¹⁾

⁽²⁾

⁽³⁾	The period of delinquency is based on the number of days scheduled payments are contractually past due.

⁽⁴⁾	In connection with the adoption of CECL on January 1, 2020, the $497 million premium as of December 31, 2020, associated with the loans is now included as part of the respective loan balance for this disclosure. This change is prospective in nature as prior balances are not restated under CECL.

Loan type:

(Dollars in millions)	December 31, 2020		December 31, 2019		Change
Stafford Loans	$	17,686	$	19,093	$	(1,407	)
Consolidation Loans		35,968		39,706		(3,738	)
Rehab Loans		4,918		5,295		(377	)
Total loans, gross	$	58,572	$	64,094	$	(5,522	)

4. Allowance for Loan Losses (Continued)

Private Education Loans

The key credit quality indicators are credit scores (FICO scores), loan status, loan seasoning, whether a loan is a TDR, the existence of a cosigner and school type. The FICO score is the higher of the borrower or co-borrower score and is updated at least every six months while school type is assessed at origination. The other Private Education Loan key quality indicators are updated quarterly.

	Private Education Loan Credit Quality Indicators by Origination Year
(Dollars in millions)	2020		2019		2018		2017		2016		Prior		Total			% of Total
Credit Quality Indicators
FICO Scores:
640 and above	$	4,008	$	2,964	$	1,079	$	340	$	72	$	11,746	$	20,209			91	%
Below 640		15		34		23		9		2		1,876		1,959			9
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
Loan Status:
In-school/grace/ deferment/forbearance	$	23	$	43	$	25	$	10	$	2	$	1,224	$	1,327			6	%
Current/90 days or less delinquent		3,999		2,953		1,075		338		72		12,187		20,624			93
Greater than 90 days delinquent		1		2		2		1		—		211		217			1
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
Seasoning⁽¹⁾:
1-12 payments	$	4,014	$	879	$	7	$	2	$	—	$	180	$	5,082			23	%
13-24 payments		—		2,098		243		7		1		234		2,583		12
25-36 payments		—		—		839		101		3		380		1,323			6
37-48 payments		—		—		—		236		38		584		858		4
More than 48 payments		—		—		—		—		31		11,808		11,839			53
Loans in-school/ grace/deferment		9		21		13		3		1		436		483		2
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
TDR Status:
TDR	$	1	$	14	$	23	$	31	$	11	$	8,351	$	8,431			38	%
Non-TDR		4,022		2,984		1,079		318		63		5,271		13,737			62
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
Cosigners:
With cosigner⁽²⁾	$	5	$	13	$	1	$	49	$	21	$	8,911	$	9,000			41	%
Without cosigner		4,018		2,985		1,101		300		53		4,711		13,168			59
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
School Type:
Not-for-profit	$	3,844	$	2,801	$	1,019	$	333	$	74	$	11,255	$	19,326			87	%
For-profit		179		197		83		16		—		2,367		2,842			13
Total	$	4,023	$	2,998	$	1,102	$	349	$	74	$	13,622	$	22,168			100	%
Allowance for loan losses														(1,089	)
Total loans, net													$	21,079

⁽¹⁾	Number of months in active repayment for which a scheduled payment was received.

⁽²⁾	Excluding Private Education Refinance Loans, which do not have a cosigner, the cosigner rate was 65% for total loans at December 31, 2020

4. Allowance for Loan Losses (Continued)

	Private Education Loan Credit Quality Indicators
	December 31, 2019
	TDRs					Non-TDRs
(Dollars in millions)	Balance⁽³⁾		% of Balance			Balance⁽³⁾		% of Balance
Credit Quality Indicators
Original Winning FICO Scores:
FICO 640 and above	$	8,493		92	%	$	13,687		97	%
FICO below 640		777		8			365		3
Total	$	9,270		100	%	$	14,052		100	%
School Type:
Not-for-profit	$	7,387		80	%	$	12,614		90	%
For-profit		1,883		20			1,438		10
Total	$	9,270		100	%	$	14,052		100	%
Cosigners:
With cosigner⁽¹⁾	$	5,792		62	%	$	5,184		37	%
Without cosigner		3,478		38			8,868		63
Total	$	9,270		100	%	$	14,052		100	%
Seasoning⁽²⁾:
1-12 payments	$	224		3	%	$	4,673		33	%
13-24 payments		301		3			1,570		11
25-36 payments		472		5			603		4
37-48 payments		662		7			251		2
More than 48 payments		7,262		78			6,675		48
Loans in-school/grace/deferment		349		4			280		2
Total loans, gross	$	9,270		100	%	$	14,052		100	%

⁽¹⁾	Excluding Private Education Refinance Loans, which do not have a cosigner, the cosigner rate was 63% and 67% for TDRs and non-TDRs, respectively, at December 31, 2019.

⁽²⁾	Number of months in active repayment for which a scheduled payment was received.

⁽³⁾	Balance equals the gross Private Education Loans.

4. Allowance for Loan Losses (Continued)

	Private Education Loan Delinquencies
	TDRs
	December 31, 2020						December 31, 2019
(Dollars in millions)	Balance			%			Balance			%
Loans in-school/grace/deferment⁽¹⁾	$	280					$	349
Loans in forbearance⁽²⁾		703						479
Loans in repayment and percentage of each status:
Loans current		6,952			93.4	%		7,557			89.5	%
Loans delinquent 31-60 days⁽³⁾		185			2.5			296			3.5
Loans delinquent 61-90 days⁽³⁾		114			1.5			191			2.3
Loans delinquent greater than 90 days⁽³⁾		197			2.6			398			4.7
Total TDR loans in repayment		7,448			100	%		8,442			100	%
Total TDR loans, gross		8,431						9,270
TDR loans unamortized discount⁽⁴⁾		—						(203	)
Total TDR loans		8,431						9,067
TDR loans receivable for partially charged-off loans⁽⁴⁾		—						347
TDR loans allowance for losses		(929	)					(941	)
TDR loans, net	$	7,502					$	8,473
Percentage of TDR loans in repayment					88.3	%					91.1	%
Delinquencies as a percentage of TDR loans in repayment					6.6	%					10.5	%
Loans in forbearance as a percentage of TDR loans in repayment and forbearance					8.6	%					5.4	%

⁽¹⁾	Deferment includes customers who have returned to school or are engaged in other permitted educational activities and are not yet required to make payments on their loans, e.g., residency periods for medical students or a grace period for bar exam preparation.

⁽²⁾

⁽³⁾	The period of delinquency is based on the number of days scheduled payments are contractually past due.

⁽⁴⁾

4. Allowance for Loan Losses (Continued)

	Private Education Loan Delinquencies
	Non-TDRs
	December 31, 2020						December 31, 2019
(Dollars in millions)	Balance			%			Balance			%
Loans in-school/grace/deferment⁽¹⁾	$	203					$	280
Loans in forbearance⁽²⁾		141						125
Loans in repayment and percentage of each status:
Loans current		13,335			99.6	%		13,526			99.1	%
Loans delinquent 31-60 days⁽³⁾		26			.2			53			.4
Loans delinquent 61-90 days⁽³⁾		12			.1			27			.2
Loans delinquent greater than 90 days⁽³⁾		20			.1			41			.3
Total non-TDR loans in repayment		13,393			100	%		13,647			100	%
Total non-TDR loans, gross		13,737						14,052
Non-TDR loans unamortized discount⁽⁴⁾		—						(414	)
Total non-TDR loans		13,737						13,638
Non-TDR loans receivable for partially charged-off loans⁽⁴⁾		—						241
Non-TDR loans allowance for losses		(160	)					(107	)
Non-TDR loans, net	$	13,577					$	13,772
Percentage of non-TDR loans in repayment					97.5	%					97.1	%
Delinquencies as a percentage of non-TDR loans in repayment					.4	%					.9	%
Loans in forbearance as a percentage of non-TDR loans in repayment and forbearance					1.0	%					.9	%

⁽¹⁾	Deferment includes customers who have returned to school or are engaged in other permitted educational activities and are not yet required to make payments on their loans, e.g., residency periods for medical students or a grace period for bar exam preparation.

⁽²⁾

⁽³⁾	The period of delinquency is based on the number of days scheduled payments are contractually past due.

⁽⁴⁾

Education Loans - Education Loan Portfolio by Program (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Accounts Notes And Loans Receivable [Line Items]
Ending Balance of education loans	$ 79,363	$ 86,820
Percentage to total education loans	100.00%	100.00%
Average Balance education loans	$ 84,242	$ 90,783
Average Effective Interest Rate of education loans	3.90%	5.04%
FFELP Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Ending Balance of education loans	$ 58,284	$ 64,575
Stafford Loans [Member] \| FFELP Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Ending Balance of education loans	$ 19,607	$ 21,723
Percentage to total education loans	25.00%	25.00%
Average Balance education loans	$ 20,844	$ 23,198
Average Effective Interest Rate of education loans	2.80%	4.24%
Consolidation Loans Member \| FFELP Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Ending Balance of education loans	$ 38,677	$ 42,852
Percentage to total education loans	49.00%	49.00%
Average Balance education loans	$ 40,678	$ 45,073
Average Effective Interest Rate of education loans	3.08%	4.13%
Private Education Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Ending Balance of education loans	$ 21,079	$ 22,245
Percentage to total education loans	26.00%	26.00%
Average Balance education loans	$ 22,720	$ 22,512
Average Effective Interest Rate of education loans	6.36%	7.69%

Income Taxes - Summary of Operating Loss and Credit Carryovers (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Net operating loss carryovers, Tax-Effected	$ 78
Valuation allowance, Operating loss and credit carryovers	64	$ 60
Operating Loss and Credit Carryovers	14
Federal [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryovers, Gross	53
Net operating loss carryovers, Tax-Effected	$ 11
Net operating loss, Expiration	2031
Operating Loss and Credit Carryovers	$ 11
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryovers, Gross	505
Net operating loss carryovers, Tax-Effected	$ 36
Net operating loss, Expiration	2021
Valuation allowance, Operating loss and credit carryovers	$ 33
Operating Loss and Credit Carryovers	3
State IRC § 163(j) disallowed interest expense carryovers, Gross	1,907
State IRC § 163(j) disallowed interest expense carryovers, Tax-Effected	$ 29
State IRC § 163(j) disallowed interest expense carryovers, Expiration	Indefinite
State IRC § 163(j) disallowed interest expense carryovers, Corresponding Valuation Allowance	$ 29
Federal and State [Member]
Operating Loss Carryforwards [Line Items]
Federal and State capital loss, Gross	10
Federal and State capital loss, Tax-Effected	$ 2
Federal and State capital loss, Expiration	2021
Federal and State Capital loss, Corresponding Valuation Allowance	$ 2

Stockholders' Equity - Additional Information (Detail) - $ / shares		12 Months Ended
	Jan. 27, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Common stock, shares authorized		1,125,000,000	1,125,000,000
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares issued		454,000,000	451,000,000
Common shares unissued but encumbered		23,000,000
Purchase price of common stock per share		$ 13.06	$ 12.76	$ 12.64
Common Stock Shares Outstanding [Member]
Class of Stock [Line Items]
Common stock, shares issued		186,000,000
Common shares repurchased	20,300,000	30,600,000	34,500,000	17,400,000
Purchase price of common stock per share	$ 14.77
Common Stock [Member]
Class of Stock [Line Items]
Closing price of common stock		$ 9.82

Income Taxes - Components of Provision for Income Tax Expense (Benefit) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current provision/(benefit):
Federal	$ 98	$ 78	$ 71
State	14	11	13
Foreign	(1)		3
Total current provision/(benefit)	111	89	87
Deferred provision/(benefit):
Federal	12	73	33
State	(3)	3	13
Foreign		1
Total deferred provision/(benefit)	9	77	46
Provision for income tax expense/(benefit)	$ 120	$ 166	$ 133

Derivative Financial Instruments - Impact of Derivatives on Other Comprehensive Income (Equity) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Total gains (losses) on cash flow hedges	$ (233)	$ (165)	$ 50
Net changes in cash flow hedges, net of taxes	(183)	(204)	39
Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Reclassification adjustments for derivative (gains) losses included in net income (interest expense)	$ 50	$ (39)	$ (11)