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v3.23.1

Allowance for Credit Losses - Narrative (Details) | 3 Months Ended |
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Mar. 31, 2023 USD ($) payment termChange | Jul. 01, 2006
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing receivable allowance period increase | $ 16,000,000 |
Interest rate offered to borrowers facing financial difficulty, period | 2 years |
Number of term changes | termChange | 2 |
Criteria for loans to be considered as nonperforming (greater than) | 90 days |
Tier 1 of government guarantee (at least) | 97.00% | 97.00%
Maximum amount of forbearance granted | 12 months |
Number of monthly payments required by a borrower between successive grants of forbearance | payment | 12 |
Threshold period for payment default | 60 days |
Period of loans past due that have accrued interest | 90 days |
Monthly payment that is smaller than the interest accrued on the loan in that month | $ 25 |
Private Education Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Threshold period when delinquent loans are written off | 120 days |
FFELP Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of FFELP loans insured and guaranteed (at least) | 97.00% |
Maximum |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Interest rate offered to borrowers facing financial difficulty | 4.00% |
Increments in which forbearance is granted | 2 months |
Minimum |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Increments in which forbearance is granted | 1 month |

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