Investment Securities (Schedule Of Realized Gain (Loss)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Available-for-sale securities, gross realized gains	$ 102	$ 173	$ 82
Available-for-sale securities, gross realized losses	0	(2)	(4)
Net realized gains on available-for-sale securities	102	171	78
Net realized gain on equity securities	190	107	73
Net unrealized (loss) gain on equity securities	(7)	29	92
Other gain on investments, net	$ 285	$ 307	$ 243