Condensed Consolidated Statements of Equity (Unaudited) - USD ($) $ in Millions		Total	Common Stock [member]	Additional Paid-in Capital [member]	Retained Earnings [member]	Accumulated Other Comprehensive Loss [member]	Non-Controlling Interests [member]
Balance at Dec. 31, 2019		$ 6,451	$ 2	$ 4,575	$ 1,922	$ (3)	$ (45)
Balance (shares) at Dec. 31, 2019			239,000,000
Share-based compensation, net		(4)		(5)	1
Net loss		(689)			(688)		(1)
Other comprehensive income (loss)		(2)				(2)
Dividends and dividend equivalents	[1]	(106)			(106)
Distributions to noncontrolling interests		(1)					(1)
Repurchase of common stock		(66)		(66)
Repurchases of common stock (Shares)			(4,000,000)
Balance at Mar. 31, 2020		5,583	$ 2	4,504	1,129	(5)	(47)
Balance (shares) at Mar. 31, 2020			235,000,000
Balance at Dec. 31, 2019		6,451	$ 2	4,575	1,922	(3)	(45)
Balance (shares) at Dec. 31, 2019			239,000,000
Net loss		(950)
Other comprehensive income (loss)		(3)
Balance at Jun. 30, 2020		5,326	$ 2	4,508	871	(6)	(49)
Balance (shares) at Jun. 30, 2020			236,000,000
Balance at Mar. 31, 2020		5,583	$ 2	4,504	1,129	(5)	(47)
Balance (shares) at Mar. 31, 2020			235,000,000
Share-based compensation, net		5		4	1
Share-based compensation, net (Shares)			1,000,000
Net loss		(261)			(259)		(2)
Other comprehensive income (loss)		(1)				(1)
Balance at Jun. 30, 2020		5,326	$ 2	4,508	871	(6)	(49)
Balance (shares) at Jun. 30, 2020			236,000,000
Balance at Dec. 31, 2020		$ 4,843	$ 2	4,519	376	(4)	(50)
Balance (shares) at Dec. 31, 2020		235,915,749	236,000,000
Share-based compensation, net				1	(1)
Net loss		$ (191)			(190)		(1)
Other comprehensive income (loss)		1				1
Balance at Mar. 31, 2021		4,653	$ 2	4,520	185	(3)	(51)
Balance (shares) at Mar. 31, 2021			236,000,000
Balance at Dec. 31, 2020		$ 4,843	$ 2	4,519	376	(4)	(50)
Balance (shares) at Dec. 31, 2020		235,915,749	236,000,000
Net loss		$ (305)
Other comprehensive income (loss)		1
Balance at Jun. 30, 2021		$ 4,545	$ 2	4,525	70	(3)	(49)
Balance (shares) at Jun. 30, 2021		236,493,847	236,000,000
Balance at Mar. 31, 2021		$ 4,653	$ 2	4,520	185	(3)	(51)
Balance (shares) at Mar. 31, 2021			236,000,000
Share-based compensation, net		6		5	1
Net loss		(114)			(116)		2
Other comprehensive income (loss)		0
Balance at Jun. 30, 2021		$ 4,545	$ 2	$ 4,525	$ 70	$ (3)	$ (49)
Balance (shares) at Jun. 30, 2021		236,493,847	236,000,000

[1] Dividends declared per common share were $0.45 for the three months ended March 31, 2020.