Fair Value Measurement (Fair Value Assets And Liabilities Measured On Nonrecurring Basis) (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	$ 11,354	$ 11,717
Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	277	291
Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	10,972	11,327
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	105	99
Fair Value, Nonrecurring \| Loans and leases
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets measured at fair value	78	48
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	$ 78	$ 48

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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