Investment Securities (Schedule Of Realized Gain (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Investments, Debt and Equity Securities [Abstract]
Gross realized gains	$ 0	$ 3	$ 5	$ 21
Net realized gain on available-for-sale securities	0	3	5	21
Net realized gain on equity securities	1	10	6	62
Net unrealized gain (loss) on equity securities	25	(137)	89	(202)
Other gain (loss) on investments, net	$ 26	$ (124)	$ 100	$ (119)