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Asset Quality - Schedule of Amortized Cost Basis of Modified Loans That Subsequently Defaulted (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | $ 27 | $ 37 | $ 11
Interest Rate Reduction |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 11 | 0
Term Extension |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 20 | 22 | 7
Other |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 6 | 0 | 1
Combination |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 1 | 4 | 3
Total commercial loans |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 25 | 34 | 11
Total commercial loans | Interest Rate Reduction |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 11 | 0
Total commercial loans | Term Extension |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 20 | 22 | 7
Total commercial loans | Other |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 5 | 0 | 1
Total commercial loans | Combination |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 1 | 3
Total commercial loans | Commercial and Industrial |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 7 | 23 | 10
Total commercial loans | Commercial and Industrial | Interest Rate Reduction |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 | 0
Total commercial loans | Commercial and Industrial | Term Extension |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 2 | 22 | 7
Total commercial loans | Commercial and Industrial | Other |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 5 | 0 | 0
Total commercial loans | Commercial and Industrial | Combination |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 1 | 3
Total commercial loans | Real estate — commercial mortgage |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 18 | 11 | 1
Total commercial loans | Real estate — commercial mortgage | Interest Rate Reduction |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 11 | 0
Total commercial loans | Real estate — commercial mortgage | Term Extension |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 18 | 0 | 0
Total commercial loans | Real estate — commercial mortgage | Other |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 |  | 1
Total commercial loans | Real estate — commercial mortgage | Combination |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 | 0
Total commercial loans | Commercial real estate loans |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 18 | 11 | 11
Total commercial loans | Commercial real estate loans | Interest Rate Reduction |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 11 | 0
Total commercial loans | Commercial real estate loans | Term Extension |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 18 | 0 | 7
Total commercial loans | Commercial real estate loans | Other |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 | 1
Total commercial loans | Commercial real estate loans | Combination |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 | 3
Total commercial loans | Commercial lease financing |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment |  |  | 0
Total commercial loans | Commercial lease financing | Interest Rate Reduction |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment |  |  | 0
Total commercial loans | Commercial lease financing | Term Extension |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment |  |  | 0
Total commercial loans | Commercial lease financing | Other |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment |  |  | 0
Total commercial loans | Commercial lease financing | Combination |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment |  |  | 0
Total consumer loans |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 2 | 3 | 0
Total consumer loans | Interest Rate Reduction |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 | 0
Total consumer loans | Term Extension |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 | 0
Total consumer loans | Other |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 1 | 0 | 0
Total consumer loans | Combination |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 1 | 3 | $ 0
Total consumer loans | Real estate — residential mortgage |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 1 | 1 |
Total consumer loans | Real estate — residential mortgage | Interest Rate Reduction |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 |
Total consumer loans | Real estate — residential mortgage | Term Extension |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 |
Total consumer loans | Real estate — residential mortgage | Other |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 |
Total consumer loans | Real estate — residential mortgage | Combination |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 1 | 1 |
Total consumer loans | Home equity loans |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 1 | 2 |
Total consumer loans | Home equity loans | Interest Rate Reduction |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 |
Total consumer loans | Home equity loans | Term Extension |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 0 | 0 |
Total consumer loans | Home equity loans | Other |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | 1 | 0 |
Total consumer loans | Home equity loans | Combination |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Financial receivable, modifications, subsequent default, recorded investment | $ 0 | $ 2 |

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