Consolidated Statements of Equity - USD ($) $ in Millions		Total	Cumulative Effect of Change in Accounting Principle [member]	Common Stock [member]	Additional Paid-in Capital [member]	Retained Earnings [member]	Retained Earnings [member] Cumulative Effect of Change in Accounting Principle [member]	Accumulated Other Comprehensive (Loss) Income [member]	Non-Controlling Interests [member]
Balance at Dec. 31, 2017		$ 5,962		$ 2	$ 3,825	$ 2,229		$ (45)	$ (49)
Balance (shares) at Dec. 31, 2017				215,000,000
Share-based compensation, net		14			14
Net income (loss)		477				472			5
Other comprehensive income (loss)		39						39
Dividends and dividend equivalents	[1]	(556)				(556)
Repurchase of common stock		(348)			(250)	(98)
Repurchases of common stock (Shares)				(14,000,000)
Distributions to noncontrolling interests		(2)							(2)
Balance at Dec. 31, 2018		5,586		$ 2	3,589	2,047		(6)	(46)
Balance (shares) at Dec. 31, 2018				201,000,000
Issuance of common stock		$ 978			978
Issuance of common stock (Shares)		978		38,000,000
Share-based compensation, net		$ 8			8
Net income (loss)		316				306			10
Other comprehensive income (loss)		3						3
Dividends and dividend equivalents		(423)				(423)
Distributions to noncontrolling interests		(9)							(9)
Balance at Dec. 31, 2019		$ 6,451	$ (8)	$ 2	4,575	1,922	$ (8)	(3)	(45)
Balance (shares) at Dec. 31, 2019		239,386,877		239,000,000
Share-based compensation, net		$ 10			10
Share-based compensation, net (Shares)				1,000,000
Net income (loss)		(1,444)				(1,440)			(4)
Other comprehensive income (loss)		(1)						(1)
Dividends and dividend equivalents		(106)				(106)
Repurchase of common stock		(66)			(66)
Repurchases of common stock (Shares)				(4,000,000)
Distributions to noncontrolling interests		(1)							(1)
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

[1] Dividends declared per common share were $1.99, $1.90 and $0.45 for the years ended December 31, 2018, December 31, 2019, and December 31, 2020, respectively. Additional special cash dividends totaling $0.75 per common share were declared for the year ended December 31, 2018.