Allowance for Credit Losses - Amortized Cost Basis of Financing Receivables that Subsequently Defaulted (Details) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Threshold period for payment default	60 days
Modified Loans	$ 290
Payment Default	287
Private Education Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Modified Loans	290
Payment Default	$ 287

Financing Receivable, Threshold Period For Payment Default

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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.

+ References

No definition available.

+ Details

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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