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Fair Value of Assets & Liabilities - Schedule of Changes In Fair Value Of Assets And Liabilities Which Fair Value Option Included In Current Period Earnings (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Mortgage Banking Noninterest Income | Loans held for sale |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Changes in fair value included in net income | $ 1 | $ (9) | $ (10)

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