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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, 2021 | Dec. 31, 2020
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Unused Commitments to Extend Credit |  |
Loss contingency, estimate of possible loss, maximum | $ 29,464 | $ 26,740
Commercial And Other | Unused Commitments to Extend Credit |  |
Loss contingency, estimate of possible loss, maximum | 25,910 | 23,443
Bankcard, Revolving Check Credit And Home Equity Loan Commitments | Unused Commitments to Extend Credit |  |
Loss contingency, estimate of possible loss, maximum | 3,554 | 3,297
Standby Letters Of Credit |  |
Loss contingency, estimate of possible loss, maximum | 3,378 | 3,273
Commercial Letters Of Credit |  |
Loss contingency, estimate of possible loss, maximum | $ 44 | $ 30

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