Income Taxes Level 4 (Details) - Components of Income Tax Expense - USD ($) $ in Millions		6 Months Ended		12 Months Ended
		Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2018
Current [Abstract]
Federal		$ (1)	$ 36	$ (14)	$ (4)
State and local		4	13	0	1
Foreign		1	11	22	25
Total current		4	60	8	22
Deferred [Abstract]
Federal		9	(2)	3	1
State and local		1	0	(1)	0
Foreign		(24)	143	4	8
Total deferred		(14)	141	6	9
Income tax expense (benefit) (1)	[1]	$ (10)	$ 201	$ 14	$ 31
Federal Statutory Income Tax Rate		21.00%	21.00%	21.00%	21.00%
Income tax expense (benefit)		$ 1	$ 21	$ 1	$ 9

[1] Excludes income tax expense of $1, $1, $21, and $9 for the year ended December 31, 2020, the Successor period July 2, 2019 through December 31, 2019, the Predecessor period January 1, 2019 through July 1, 2019, and the year ended December 31, 2018, respectively, related to the Held for Sale Business.