Derivative And Credit-Related Financial Instruments (Schedule Of Net Gains Recognized In Income On Customer-Initiated Derivatives) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	$ 22	$ 30
Customer-initiated and other activities
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	22	30
Interest rate contracts | Customer-initiated and other activities | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	9	15
Energy contracts | Customer-initiated and other activities | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	2	4
Foreign exchange contracts | Customer-initiated and other activities | Foreign exchange income
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	$ 11	$ 11