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Mortgage Servicing Rights - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
FDIC Serviced Loans | Loan administration income on mortgage loans subserviced |  |
Servicing Assets at Fair Value [Line Items] |  |
Servicing fees, ancillary income and late fees | $ 10 | $ 95

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