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v3.25.2

Allowance for Loan Losses - Loan Type (Detail) - FFELP Loans [Member] - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024
Financing Receivable Recorded Investment Past Due [Line Items] |  |
Total loans, gross | $ 29,800 | $ 33,134
Change | (3,334) |
Stafford Loans [Member] |  |
Financing Receivable Recorded Investment Past Due [Line Items] |  |
Total loans, gross | 9,703 | 10,589
Change | (886) |
Consolidation Loans [Member] |  |
Financing Receivable Recorded Investment Past Due [Line Items] |  |
Total loans, gross | 17,077 | 19,273
Change | (2,196) |
Rehab Loans [Member] |  |
Financing Receivable Recorded Investment Past Due [Line Items] |  |
Total loans, gross | 3,020 | $ 3,272
Change | $ (252) |

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