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v3.25.2

Allowance for Loan Losses - Amortized Cost Basis of Loans Modified to Borrowers with Financial Difficulty (Details) - Private Education Loans [Member] - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Interest Rate Concession [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Loan Modifications, Amortized Cost | $ 568 | $ 601 | $ 1,171 | $ 1,143
Loan Modifications, % of Loan Type | 3.60% | 3.60% | 7.40% | 6.80%
Loans receivable, weighted average rate of interest | 12.30% | 13.30% | 12.40% | 13.30%
Loans receivable, weighted average rate of interest after reduction | 5.30% | 5.50% | 5.40% | 5.50%
More Than an Insignificant Payment Delay [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Loan Modifications, Amortized Cost | $ 295 | $ 314 | $ 548 | $ 597
Loan Modifications, % of Loan Type | 1.90% | 1.90% | 3.50% | 3.60%
Loans receivable, weighted average period added to remaining life of loan | 5 months | 5 months | 7 months | 6 months
Combination Rate Reduction and Term Extension [Member] |  |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |  |
Loan Modifications, Amortized Cost | $ 35 | $ 39 | $ 75 | $ 78
Loan Modifications, % of Loan Type | 0.20% | 0.20% | 0.50% | 0.50%
Loans receivable, weighted average rate of interest | 12.10% | 12.70% | 12.00% | 12.80%
Loans receivable, weighted average rate of interest after reduction | 5.40% | 5.30% | 5.40% | 5.30%
Loans receivable, weighted average period added to remaining life of loan | 7 years | 7 years | 7 years | 7 years

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