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Fair Value Measurement (Fair Value Assets And Liabilities Measured On Nonrecurring Basis) (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	$ 11,730	$ 8,811
Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	289	381
Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	11,340	8,322
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	101	108
Fair Value, Nonrecurring | Loans and leases
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	17	28
Fair Value, Nonrecurring | Loans and leases | Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	0	0
Fair Value, Nonrecurring | Loans and leases | Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	0	0
Fair Value, Nonrecurring | Loans and leases | Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	$ 17	$ 28

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- Definition

Fair value portion of asset recognized for present right to economic benefit.

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