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Derivatives - Schedule of Derivatives Associated With Interest Rate Risk Management Activities (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Customer interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | $ 4,067 | $ 3,076
Assets | 22 | 3
Liabilities | 197 | 270
Offsetting upstream interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 4,273 | 3,076
Assets | 135 | 91
Liabilities | 23 | 6
Customer Interest Rate Contracts Hedging | Hedging Instruments And Hedged Items | Customer interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 8,375 | 8,377
Assets | 21 | 3
Liabilities | 392 | 570
Customer Interest Rate Contracts Hedging | Hedging Instruments And Hedged Items | Offsetting upstream interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 8,375 | 8,377
Assets | 389 | 351
Liabilities | $ 22 | $ 5

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