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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, 2023 | Dec. 31, 2022
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Unused Commitments to Extend Credit |  |
Loss contingency, estimate of possible loss, maximum | $ 31,385 | $ 34,817
Commercial And Other | Unused Commitments to Extend Credit |  |
Loss contingency, estimate of possible loss, maximum | 27,303 | 30,800
Bankcard, Revolving Check Credit And Home Equity Loan Commitments | Unused Commitments to Extend Credit |  |
Loss contingency, estimate of possible loss, maximum | 4,082 | 4,017
Standby Letters Of Credit |  |
Loss contingency, estimate of possible loss, maximum | 3,586 | 3,712
Commercial Letters Of Credit |  |
Loss contingency, estimate of possible loss, maximum | $ 48 | $ 39

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