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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 | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | $ 1,231 | $ 1,375
Loans held-for-sale | 88 | 51
Securities available for sale at fair value | 8,100 | 8,836
Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Loans held-for-sale | 88 | 51
Securities available for sale at fair value | 8,100 | 8,836
Total other assets | 985 | 594
Total assets | 10,404 | 10,856
Total other liabilities | 1,102 | 958
Total liabilities | 1,468 | 1,293
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 | 132 | 143
Total assets | 132 | 143
Total other liabilities | 8 | 8
Total liabilities | 8 | 8
Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Loans held-for-sale | 67 | 29
Securities available for sale at fair value | 8,100 | 8,836
Total other assets | 853 | 451
Total assets | 10,228 | 10,666
Total other liabilities | 1,068 | 923
Total liabilities | 1,434 | 1,258
Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Loans held-for-sale | 21 | 22
Securities available for sale at fair value | 0 | 0
Total other assets | 0 | 0
Total assets | 44 | 47
Total other liabilities | 26 | 27
Total liabilities | 26 | 27
Deferred compensation mutual funds | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 99 | 112
Deferred compensation mutual funds | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 99 | 112
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 | 23 | 22
Equity, mutual funds, and other | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 23 | 22
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 | 10 | 9
Total other liabilities | 8 | 8
Derivatives, forwards and futures | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets | 10 | 9
Total other liabilities | 8 | 8
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 | 853 | 449
Total other liabilities | 1,068 | 922
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 | 853 | 449
Total other liabilities | 1,068 | 922
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 assets |  | 2
Total other liabilities | 26 | 28
Derivatives, other | Level 1 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets |  | 0
Total other liabilities | 0 | 0
Derivatives, other | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets |  | 2
Total other liabilities | 0 | 1
Derivatives, other | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Total other assets |  | 0
Total other liabilities | 26 | 27
Government agency issued MBS | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Securities available for sale at fair value | 4,325 | 4,763
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 | 4,325 | 4,763
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 | 2,100 | 2,313
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 | 2,100 | 2,313
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 | 1,128 | 1,163
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 | 1,128 | 1,163
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 | 547 | 597
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 | 547 | 597
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 | 1,231 | 1,375
Total trading liabilities | 366 | 335
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 | 1,208 | 1,350
Total trading liabilities | 366 | 335
Specialty Banking | Level 3 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 23 | 25
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 | 24 | 101
Total trading liabilities | 301 | 275
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 | 24 | 101
Total trading liabilities | 301 | 275
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 | 53 | 144
Total trading liabilities | 1 | 2
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 | 0
Specialty Banking | Government agency issued MBS | Level 2 | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 53 | 144
Total trading liabilities | 1 | 2
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 | 0
Specialty Banking | Government agency issued CMO | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 94 | 61
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 | 94 | 61
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 | 252 | 115
Total trading liabilities | 9 |
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
Total trading liabilities | 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 | 252 | 115
Total trading liabilities | 9 |
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
Total trading liabilities | 0 |
Specialty Banking | States and municipalities | Recurring |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |
Trading securities | 26 | 54
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 | 26 | 54
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 | 759 | 875
Total trading liabilities | 55 | 58
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 | 759 | 875
Total trading liabilities | 55 | 58
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 | 23 | 25
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 | $ 23 | $ 25

X
- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479130/326-30-45-1 + Details
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