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Derivatives - Derivatives Associated With Interest Rate Risk Management Activities (Details) - USD ($) $ in Millions | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Customer interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | $ 4,173 | $ 4,067
Assets | 9 | 22
Liabilities | 232 | 197
Offsetting upstream interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 4,380 | 4,273
Assets | 166 | 135
Liabilities | 10 | 23
Customer Interest Rate Contracts Hedging | Hedging Instruments And Hedged Items | Customer interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 8,290 | 8,375
Assets | 7 | 21
Liabilities | 465 | 392
Customer Interest Rate Contracts Hedging | Hedging Instruments And Hedged Items | Offsetting upstream interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 8,290 | 8,375
Assets | 462 | 389
Liabilities | $ 8 | $ 22

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