Investment And Other Income (Components Of Investment And Other Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Investment And Other Income [Abstract]
Interest and dividend income	$ 17	$ 6	$ 38	$ 8
Pension benefit	5	25	9	50
OPEB costs	(2)	(5)	(5)	(8)
OPEB remeasurement gain (loss)	12	96	(8)	150
All other, net				(1)
Total investment and other income, net	$ 32	$ 122	$ 34	$ 199