Investment and Other Income (Loss), Net (Components Of Investment And Other Income (Loss)) (Details) - USD ($) $ in Millions	4 Months Ended	8 Months Ended	12 Months Ended
	Apr. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Successor [Member]
Interest and dividend income		$ 1
Pension and OPEB benefit (costs)		2
All other, net		(8)
Investment and other income (loss), net		$ (5)
Predecessor [Member]
Interest and dividend income			$ 4	$ 9
Pension and OPEB benefit (costs)	2		(43)	(42)
All other, net	(1)		(4)	(4)
Investment and other income (loss), net	$ 1		$ (43)	$ (37)