Condensed Consolidated Statement of Equity (Deficit) - USD ($) $ in Millions	Total	Common Stock [Member]	Paid-in Capital [Member]	Treasury Stock [Member]	Notes Receivable From Parent [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Deficit [Member]	Parent [Member]	Noncontrolling Interest [Member]
Balance at Dec. 31, 2018	$ (2,914)	$ 1	$ 526	$ (296)	$ 0	$ (18)	$ (3,125)	$ (2,912)	$ (2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Elimination of Predecessor AOCI	26
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	2,894	0	0	0	0	0	(160)	(160)	1
Net Income (Loss) Attributable to Parent	2,895
Net Income (Loss) Attributable to Parent - Predecessor	(159)
Other comprehensive income	(8)	0	0	0	0	(8)	0	(8)	0
Return of Capital from parent	0
Balance at Jun. 30, 2019	(3,081)	1	526	(296)	0	(26)	(3,285)	(3,080)	(1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Elimination of Predecessor Equity	0	(1)	(526)	296	0	0	231	0	0
Elimination of Predecessor AOCI	26	0	0	0	0	26	0	26	0
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	3,054
Net Income (Loss) Attributable to Parent	3,054	0	0	0	0	0	3,054	3,054	0
Stock Issued During Period, Value, New Issues	1,157	0	1,157	0	0	0	0	1,157	0
Other comprehensive income	0
Balance at Jul. 01, 2019	(1)	0	0	0	0	0	0	0	(1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(43)	0	0	0	0	0	(43)	(43)	0
Net Income (Loss) Attributable to Parent	(43)
Employee Benefits and Share-based Compensation	5	0		0	0	0	0	5	0
Other comprehensive income	(16)	0	0	0	0	(16)	0	(16)	0
Return of Capital from parent	0
Balance at Sep. 30, 2019	1,102	0	1,162	0	0	(16)	(43)	1,103	(1)
Balance at Dec. 31, 2019	1,075	0	1,165	0	0	(1)	(89)	1,075	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(203)	0	0	0	0	0	(203)	(203)	0
Net Income (Loss) Attributable to Parent	(203)
Employee Benefits and Share-based Compensation	13	0		0	0	0	0	13	0
Other comprehensive income	(48)	0	0	0	0	(48)	0	(48)	0
Return of Capital from parent	(10)	0	(10)	0	0	0	0	(10)	0
Due from Officers or Stockholders, Noncurrent	(10)	0	0	0	(10)	0	0	(10)	0
Settlement of affiliate loan	10	0	0	0		0	0	10	0
Balance at Sep. 30, 2020	827	0	1,168	0	0	(49)	(292)	827	0
Balance at Jun. 30, 2020	919	0	1,164	0	0	(55)	(190)	919	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(102)	0	0	0	0	0	(102)	(102)	0
Net Income (Loss) Attributable to Parent	(102)
Employee Benefits and Share-based Compensation	4	0		0	0	0	0	4	0
Other comprehensive income	6	0	0	0	0	6	0	6	0
Balance at Sep. 30, 2020	$ 827	$ 0	$ 1,168	$ 0	$ 0	$ (49)	$ (292)	$ 827	$ 0