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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
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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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