Revenue Recognition (Changes In Contract Assets And Contract Liabilities) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Successor [Member]
Contract current liabilities, Beginning balance	$ 27
Contract current liabilities, Revenue recognized included in opening contract balance	(9)
Contract current liabilities, Credits granted, excluding amounts recognized as revenue	9
Contract current liabilities, Ending balance	27
Contract noncurrent liabilities, Beginning balance	11
Contract noncurrent liabilities, Revenue recognized included in opening contract balance	(3)
Contract noncurrent liabilities, Credits granted, excluding amounts recognized as revenue	5
Contract noncurrent liabilities, Ending balance	$ 13
Predecessor [Member]
Contract current assets, Beginning balance		$ 6
Contract current assets, Revenue recognized included in opening contract balance		(4)
Contract current assets, Ending balance		2
Contract noncurrent assets, Beginning balance		9
Contract noncurrent assets, Ending balance		9
Contract current liabilities, Beginning balance		58
Contract current liabilities, Revenue recognized included in opening contract balance		(17)
Contract current liabilities, Cash received, excluding amounts recognized as revenue		17
Contract current liabilities, Ending balance		58
Contract noncurrent liabilities, Beginning balance		20
Contract noncurrent liabilities, Revenue recognized included in opening contract balance		(2)
Contract noncurrent liabilities, Cash received, excluding amounts recognized as revenue		1
Contract noncurrent liabilities, Ending balance		$ 19