Criteria for loans to be considered as nonperforming.

No definition available.

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- Definition

Financing Receivable, Credit Loss, Expense (Reversal), Reduction

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No definition available.

+ Details

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- Definition

Fixed-Pay Loan, Monthly Payment Amount, Below Monthly Accrued Interest

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No definition available.

+ Details

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- Definition

Loans And Leases Receivable, Percentage Of Loans In Full And Interest Repayment Status That Are Subject To Interest Rate Reductions

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No definition available.

+ Details

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- Definition

Loans And Leases Receivable, Period Of Interest Rate Reduction, Financial Difficulty Status

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No definition available.

+ Details

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- Definition

Loans And Leases Receivable, Temporary Interest Rate Reduction, Financial Difficulty Status

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No definition available.

+ Details

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- Definition

Loans and Leases Receivable, Impaired, Loans Granted Forbearance Qualified as Trouble Debt Restructuring

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No definition available.

+ Details

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- Definition

Loans and Leases Receivable, Percentage of FFELP Loans Insured and Guaranteed

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No definition available.

+ Details

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- Definition

Payment Default Period For Troubled Debt Restructurings

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No definition available.

+ Details

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- Definition

Period of Loans Past Due That Have Accrued Interest

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No definition available.

+ Details

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- Definition

Tier One of Government Guarantee

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No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount of credit loss expense (reversal of expense) for financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(11))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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Allowance for Credit Losses - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Jul. 01, 2006
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for credit losses	$ 69,677,000	$ 351,887,000	$ (156,090,000)	$ 413,145,000
Reduction to provision for credit losses			$ 569,000,000	$ (397,000,000)
Interest rate offered to borrowers facing financial difficulty	4.00%		4.00%
Interest rate offered to borrowers facing financial difficulty, period			2 years
Percentage of loans in full and interest repayment status that are subject to interest rate reductions	9.00%	8.90%	9.00%	8.90%
Percentage of loans granted forbearance (as a percentage)	47.00%		47.00%		47.00%
Criteria for loans to be considered as nonperforming (greater than)			90 days
Tier 1 of government guarantee (at least)	97.00%		97.00%			97.00%
TDR payment default period (more than)			60 days
Percentage of FFELP loans insured and guaranteed (at least)			97.00%
Period of loans past due that have accrued interest (greater than)			90 days
Monthly payment that is smaller than the interest accrued on the loan in that month			$ 25
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest rate offered to borrowers facing financial difficulty	4.00%		4.00%