CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) shares in Thousands, $ in Millions	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Noncontrolling Interests [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member]	Total
Beginning balance at Dec. 31, 2019	$ 6	$ 5,049	$ (2)	$ 10,592	$ (8)	$ (8,571)	$ 2	$ (2)	$ 7,070
Beginning balance, shares at Dec. 31, 2019	630,282					(205,956)
Equity roll forward
Consolidated net income				1,058					1,058
Other comprehensive income (loss), net of tax					(8)				(8)
Cash dividends declared				(696)					(696)
Equity-based compensation transactions, net		55		1		$ 82			138
Equity-based compensation transactions, net, shares						1,945
Common stock repurchase program						$ (402)			(402)
Common stock repurchase program, shares						(3,687)
Other, net				(1)					(1)
Other, net, shares						3
Ending balance at Sep. 30, 2020	$ 6	5,104		10,952	(16)	$ (8,891)	2		7,157
Ending balance, shares at Sep. 30, 2020	630,282					(207,695)
Beginning balance at Jun. 30, 2020	$ 6	5,040		10,795	(41)	$ (8,909)	2		6,893
Beginning balance, shares at Jun. 30, 2020	630,282					(208,118)
Equity roll forward
Consolidated net income				390					390
Other comprehensive income (loss), net of tax					25				25
Cash dividends declared				(230)					(230)
Equity-based compensation transactions, net		64		(2)		$ 18			80
Equity-based compensation transactions, net, shares						422
Other, net				(1)					(1)
Other, net, shares						1
Ending balance at Sep. 30, 2020	$ 6	5,104		10,952	(16)	$ (8,891)	2		7,157
Ending balance, shares at Sep. 30, 2020	630,282					(207,695)
Beginning balance at Dec. 31, 2020	$ 6	5,129		11,159	39	$ (8,881)	2		7,454
Beginning balance, shares at Dec. 31, 2020	630,282					(207,481)
Equity roll forward
Consolidated net income				1,310			1		1,311
Other comprehensive income (loss), net of tax					(27)				(27)
Cash dividends declared				(730)					(730)
Equity-based compensation transactions, net		82		1		$ 84			167
Equity-based compensation transactions, net, shares						1,957
Common stock repurchase program		(100)				$ (900)			(1,000)
Common stock repurchase program, shares						(6,472)
Other, net							(1)		(1)
Ending balance at Sep. 30, 2021	$ 6	5,111		11,740	12	$ (9,697)	2		7,174
Ending balance, shares at Sep. 30, 2021	630,282					(211,996)
Beginning balance at Jun. 30, 2021	$ 6	5,104		11,444	70	$ (9,272)	2		7,354
Beginning balance, shares at Jun. 30, 2021	630,282					(209,467)
Equity roll forward
Consolidated net income				538			1		539
Other comprehensive income (loss), net of tax					(58)				(58)
Cash dividends declared				(241)					(241)
Equity-based compensation transactions, net		57		(1)		$ 25			81
Equity-based compensation transactions, net, shares						558
Common stock repurchase program		(50)				$ (450)			(500)
Common stock repurchase program, shares						(3,087)
Other, net							(1)		(1)
Ending balance at Sep. 30, 2021	$ 6	$ 5,111		$ 11,740	$ 12	$ (9,697)	$ 2		$ 7,174
Ending balance, shares at Sep. 30, 2021	630,282					(211,996)