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Fair Value of Assets and Liabilities - Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis (Details) - USD ($) $ in Millions | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | $ 1,161 | $ 1,412
Loans held-for-sale | 84 | 68
Securities available for sale at fair value | 8,148 | 8,391
Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Loans held-for-sale | 84 | 68
Securities available for sale at fair value | 8,148 | 8,391
Total other assets | 791 | 713
Total assets | 10,184 | 10,584
Total other liabilities | 816 | 699
Total liabilities | 1,283 | 1,208
Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Loans held-for-sale | 0 | 0
Securities available for sale at fair value | 0 | 0
Total other assets | 146 | 145
Total assets | 146 | 145
Total other liabilities | 4 | 10
Total liabilities | 4 | 10
Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Loans held-for-sale | 70 | 42
Securities available for sale at fair value | 8,148 | 8,391
Total other assets | 645 | 568
Total assets | 10,005 | 10,400
Total other liabilities | 792 | 666
Total liabilities | 1,259 | 1,175
Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Loans held-for-sale | 14 | 26
Securities available for sale at fair value | 0 | 0
Total other assets | 0 | 0
Total assets | 33 | 39
Total other liabilities | 20 | 23
Total liabilities | 20 | 23
Deferred compensation mutual funds | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 107 | 102
Deferred compensation mutual funds | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 107 | 102
Deferred compensation mutual funds | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 0 | 0
Deferred compensation mutual funds | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 0 | 0
Equity, mutual funds, and other | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 34 | 34
Equity, mutual funds, and other | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 34 | 34
Equity, mutual funds, and other | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 0 | 0
Equity, mutual funds, and other | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 0 | 0
Derivatives, forwards and futures | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 5 | 9
Total other liabilities | 4 | 10
Derivatives, forwards and futures | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 5 | 9
Total other liabilities | 4 | 10
Derivatives, forwards and futures | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 0 | 0
Total other liabilities | 0 | 0
Derivatives, forwards and futures | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 0 | 0
Total other liabilities | 0 | 0
Derivatives, interest rate contracts | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 645 | 568
Total other liabilities | 791 | 666
Derivatives, interest rate contracts | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 0 | 0
Total other liabilities | 0 | 0
Derivatives, interest rate contracts | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 645 | 568
Total other liabilities | 791 | 666
Derivatives, interest rate contracts | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 0 | 0
Total other liabilities | 0 | 0
Derivatives, other | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other liabilities | 21 | 23
Derivatives, other | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other liabilities | 0 | 0
Derivatives, other | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other liabilities | 1 | 0
Derivatives, other | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other liabilities | 20 | 23
Government agency issued MBS | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 4,351 | 4,484
Government agency issued MBS | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 0 | 0
Government agency issued MBS | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 4,351 | 4,484
Government agency issued MBS | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 0 | 0
Government agency issued CMO | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 2,085 | 2,146
Government agency issued CMO | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 0 | 0
Government agency issued CMO | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 2,085 | 2,146
Government agency issued CMO | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 0 | 0
Other U.S. government agencies | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 1,133 | 1,172
Other U.S. government agencies | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 0 | 0
Other U.S. government agencies | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 1,133 | 1,172
Other U.S. government agencies | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 0 | 0
States and municipalities | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 579 | 589
States and municipalities | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 0 | 0
States and municipalities | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 579 | 589
States and municipalities | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 0 | 0
Specialty Banking | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 1,161 | 1,412
Total trading liabilities | 467 | 509
Specialty Banking | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Total trading liabilities | 0 | 0
Specialty Banking | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 1,142 | 1,399
Total trading liabilities | 467 | 509
Specialty Banking | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 19 | 13
Total trading liabilities | 0 | 0
Specialty Banking | U.S. treasuries | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 6 | 3
Total trading liabilities | 379 | 426
Specialty Banking | U.S. treasuries | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Total trading liabilities | 0 | 0
Specialty Banking | U.S. treasuries | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 6 | 3
Total trading liabilities | 379 | 426
Specialty Banking | U.S. treasuries | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Total trading liabilities | 0 | 0
Specialty Banking | Government agency issued MBS | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 78 | 114
Total trading liabilities |  | 1
Specialty Banking | Government agency issued MBS | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Total trading liabilities |  | 0
Specialty Banking | Government agency issued MBS | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 78 | 114
Total trading liabilities |  | 1
Specialty Banking | Government agency issued MBS | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Total trading liabilities |  | 0
Specialty Banking | Government agency issued CMO | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 178 | 336
Specialty Banking | Government agency issued CMO | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Specialty Banking | Government agency issued CMO | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 178 | 336
Specialty Banking | Government agency issued CMO | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Specialty Banking | Other U.S. government agencies | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 233 | 152
Specialty Banking | Other U.S. government agencies | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Specialty Banking | Other U.S. government agencies | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 233 | 152
Specialty Banking | Other U.S. government agencies | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Specialty Banking | States and municipalities | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 21 | 17
Specialty Banking | States and municipalities | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Specialty Banking | States and municipalities | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 21 | 17
Specialty Banking | States and municipalities | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Specialty Banking | Corporate and other debt | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 626 | 777
Total trading liabilities | 88 | 82
Specialty Banking | Corporate and other debt | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Total trading liabilities | 0 | 0
Specialty Banking | Corporate and other debt | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 626 | 777
Total trading liabilities | 88 | 82
Specialty Banking | Corporate and other debt | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Total trading liabilities | 0 | 0
Specialty Banking | Interest-only strips | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 19 | 13
Specialty Banking | Interest-only strips | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Specialty Banking | Interest-only strips | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 0 | 0
Specialty Banking | Interest-only strips | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | $ 19 | $ 13

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