Condensed Consolidated Statement of Equity (Deficit) - USD ($) $ in Millions	Total	Common Stock [Member]	Paid-in Capital [Member]	Notes Receivable From Parent [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2019	$ 1,075	$ 0	$ 1,165	$ 0	$ (1)	$ (89)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Settlement of affiliate loan	10
Balance at Mar. 31, 2020	954	0	1,170	(10)	(58)	(148)
Balance at Dec. 31, 2019	1,075	0	1,165	0	(1)	(89)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent	(101)
Net income (loss)	(101)	0	0	0	0	(101)
Employee Benefits and Share-based Compensation	9	0	9	0	0	0
Other comprehensive income	(54)	0	0	0	(54)	0
Return of Capital from parent	(10)	0	(10)	0	0	0
Disbursement of affiliate loan	(10)	0	0	(10)	0	0
Settlement of affiliate loan	10	0	0	10	0	0
Balance at Jun. 30, 2020	919	0	1,164	0	(55)	(190)
Balance at Mar. 31, 2020	954	0	1,170	(10)	(58)	(148)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent	(42)
Net income (loss)	(42)	0	0	0	0	(42)
Employee Benefits and Share-based Compensation	4	0		0	0	0
Other comprehensive income	3	0	0	0	3	0
Return of Capital from parent	(10)	0	(10)	0	0	0
Settlement of affiliate loan	10	0	0	10	0	0
Balance at Jun. 30, 2020	919	0	1,164	0	(55)	(190)
Balance at Dec. 31, 2020	823	0	1,169	0	(27)	(319)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent	49
Net income (loss)	49	0	0	0	0	49
Employee Benefits and Share-based Compensation	15	0	15	0	0	0
Other comprehensive income	(4)	0	0	0	(4)	0
Return of Capital from parent	0
Balance at Jun. 30, 2021	883	0	1,184	0	(31)	(270)
Balance at Mar. 31, 2021	836	0	1,175	0	(31)	(308)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent	38
Net income (loss)	38	0	0	0	0	38
Employee Benefits and Share-based Compensation	9	0	9	0	0	0
Other comprehensive income	0	0	0	0	0	0
Balance at Jun. 30, 2021	$ 883	$ 0	$ 1,184	$ 0	$ (31)	$ (270)