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Derivative And Credit-Related Financial Instruments (Schedule Of Financial Instruments With Off-Balance Sheet Credit Risk) (Details) - Maximum - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Unused Commitments to Extend Credit |  |
Loss contingency, estimate of possible loss, maximum | $ 28,397 | $ 31,385
Commercial And Other | Unused Commitments to Extend Credit |  |
Loss contingency, estimate of possible loss, maximum | 24,342 | 27,303
Bankcard, Revolving Check Credit And Home Equity Loan Commitments | Unused Commitments to Extend Credit |  |
Loss contingency, estimate of possible loss, maximum | 4,055 | 4,082
Standby Letters Of Credit |  |
Loss contingency, estimate of possible loss, maximum | 4,138 | 3,586
Commercial Letters Of Credit |  |
Loss contingency, estimate of possible loss, maximum | $ 12 | $ 48

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