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Fair Value Measurement (Losses Resulting From Nonrecurring Fair Value Adjustments) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Fair Value, Nonrecurring | Loans and leases |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Losses resulting from nonrecurring fair value adjustments | $ 17 | $ 25 | $ 72 | $ 84

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