Allowance for Credit Losses - Amortized Cost Basis of Financing Receivables that Subsequently Defaulted (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Modified Loans	$ 3,512	$ 3,963
Payment Default	3,450	3,901
Combination - Interest Rate Reduction and Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Modified Loans	3,300	3,700
Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Modified Loans	200	300
Private Education Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Modified Loans	3,512	3,963
Payment Default	$ 3,450	$ 3,901

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No definition available.

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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 https://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 https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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