Investment Securities (Schedule Of Realized Gain (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Investments, Debt and Equity Securities [Abstract]
Gross realized gains	$ 0	$ 2	$ 5	$ 23
Net realized gain on available-for-sale securities	0	2	5	23
Net realized gain on equity securities	15	5	21	67
Net unrealized (loss) gain on equity securities	(56)	(61)	33	(263)
Other (loss) gain on investments, net	$ (41)	$ (54)	$ 59	$ (173)