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Fair Value Measurements - Additional Information (Details) - USD ($) | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Loans, net of unearned income (residential) | $ 106,541,000,000 | $ 104,260,000,000
Discontinued operations | Education Lending |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Loans, net of unearned income (residential) | 205,000,000 | 257,000,000
Carrying Amount |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Loans, net of unearned income (residential) | 105,103,000,000 | 102,841,000,000
Carrying Amount | Discontinued operations | Education Lending |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Loans, net of unearned income (residential) | 205,000,000 | 257,000,000
Estimate of Fair Value Measurement |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Loans, net of unearned income (residential) | 101,946,000,000 | 99,105,000,000
Estimate of Fair Value Measurement | Discontinued operations | Education Lending |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Loans, net of unearned income (residential) | 155,000,000 | 192,000,000
Fair Value, Nonrecurring | Estimate of Fair Value Measurement |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Liabilities measured at fair value on non recurring basis | $ 0 | $ 0

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