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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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Loss Measured At Fair Value On Nonrecurring Basis

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