Shareholders' Equity Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions		1 Months Ended	11 Months Ended	12 Months Ended
	Dec. 13, 2019	Dec. 31, 2019	Dec. 13, 2019	Dec. 31, 2020	Dec. 31, 2018	Dec. 12, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Temporary Equity, Elimination as Part of Reorganization	$ 51		$ 1,697
Beginning balance	(1,697)	$ 0	(1,746)	$ 9
Other comprehensive (loss) income before reclassifications		9	40	(52)
Reclassifications			9
Ending balance	0	9	0	(43)	$ (1,746)
Other Comprehensive Income (Loss), Net of Tax		(9)	(49)	52	227
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Temporary Equity, Elimination as Part of Reorganization			1,672
Beginning balance	(1,672)	0	(1,724)	7
Other comprehensive (loss) income before reclassifications		7	52	(38)
Reclassifications			0
Ending balance	0	7	0	(31)	(1,724)
Other Comprehensive Income (Loss), Net of Tax			52
Defined Benefit Pension [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Temporary Equity, Elimination as Part of Reorganization			25
Beginning balance	(25)	0	(14)	2
Other comprehensive (loss) income before reclassifications		2	(12)	(14)
Reclassifications			1
Ending balance	0	2	0	(12)	(14)
Other Comprehensive Income (Loss), Net of Tax			(11)
Deferred Loss on Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Temporary Equity, Elimination as Part of Reorganization		0	0	0
Other comprehensive (loss) income before reclassifications			0
Reclassifications			8
Other Comprehensive Income (Loss), Net of Tax			8
Fair Value Hedging [Member] | Interest Rate Swap [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Deferred (Gain) Loss on Discontinuation of Fair Value Hedge	$ 0	$ 0	$ 0	$ 0	$ (8)	$ 0