Investment And Other Income (Components Of Investment And Other Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Successor [Member]
Interest and dividend income	$ 2,000
Pension benefit	25,000
OPEB costs	(3,000)
OPEB remeasurement	54,000
All other, net	(1,000)
Investment and other income, net	$ 77,000
Predecessor [Member]
Pension benefit		$ 4,000
OPEB costs		(3,000)
All other, net		1,000
Investment and other income, net		$ 2,000