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Derivatives - Derivatives Associated with Interest Rate Risk Management Activities (Details) - USD ($) $ in Millions | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Customer interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | $ 4,155 | $ 4,067
Assets | 7 | 22
Liabilities | 230 | 197
Customer interest rate contracts | Customer Interest Rate Contracts Hedging | Hedging Instruments And Hedged Items |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 8,427 | 8,375
Assets | 7 | 21
Liabilities | 456 | 392
Offsetting upstream interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 4,328 | 4,273
Assets | 165 | 135
Liabilities | 8 | 23
Offsetting upstream interest rate contracts | Customer Interest Rate Contracts Hedging | Hedging Instruments And Hedged Items |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 8,427 | 8,375
Assets | 453 | 389
Liabilities | $ 8 | $ 22

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