Derivative And Credit-Related Financial Instruments (Schedule Of Financial Instruments With Off-Balance Sheet Credit Risk) (Details) - Maximum - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Unused Commitments to Extend Credit
Loss contingency, estimate of possible loss	$ 30,085	$ 29,464
Commercial And Other | Unused Commitments to Extend Credit
Loss contingency, estimate of possible loss	26,471	25,910
Bankcard, Revolving Check Credit And Home Equity Loan Commitments | Unused Commitments to Extend Credit
Loss contingency, estimate of possible loss	3,614	3,554
Standby Letters Of Credit
Loss contingency, estimate of possible loss	3,391	3,378
Commercial Letters Of Credit
Loss contingency, estimate of possible loss	$ 41	$ 44