Condensed Consolidated Statements of Stockholders' Deficit - USD ($) shares in Thousands, $ in Millions	Total	Common Stock [Member]	Capital in Excess of Par Value [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Deficit [Member]	Equity Attributable to Noncontrolling Interests [Member]
Balances at Dec. 31, 2018	$ (2,918)	$ 3		$ (381)	$ (4,572)	$ 2,032
Balance, shares at Dec. 31, 2018		342,895
Comprehensive income (loss)	1,188			7	1,039	142
Repurchase of common stock	(278)		$ 32		(310)
Repurchase of common stock, shares		(2,106)
Share-based benefit plans	(29)		(29)
Share-based benefit plans, shares		2,242
Cash dividends declared	(140)				(140)
Distributions	(136)					(136)
Other	58		(3)			61
Balance at Mar. 31, 2019	(2,255)	$ 3		(374)	(3,983)	2,099
Balance, shares at Mar. 31, 2019		343,031
Balances at Dec. 31, 2018	(2,918)	$ 3		(381)	(4,572)	2,032
Balance, shares at Dec. 31, 2018		342,895
Comprehensive income (loss)	2,792
Balance at Sep. 30, 2019	(1,447)	$ 3		(461)	(3,107)	2,118
Balance, shares at Sep. 30, 2019		340,053
Balances at Mar. 31, 2019	(2,255)	$ 3		(374)	(3,983)	2,099
Balance, shares at Mar. 31, 2019		343,031
Comprehensive income (loss)	870			(57)	783	144
Repurchase of common stock	(242)		(107)		(135)
Repurchase of common stock, shares		(1,928)
Share-based benefit plans	118		118
Share-based benefit plans, shares		414
Cash dividends declared	(139)				(139)
Distributions	(111)					(111)
Other	(11)		(11)
Balance at Jun. 30, 2019	(1,770)	$ 3		(431)	(3,474)	2,132
Balance, shares at Jun. 30, 2019		341,517
Comprehensive income (loss)	734			(30)	612	152
Repurchase of common stock	(239)		(132)		(107)
Repurchase of common stock, shares		(1,846)
Share-based benefit plans	128		128
Share-based benefit plans, shares		382
Cash dividends declared	(138)				(138)
Distributions	(157)					(157)
Other	(5)		4			(9)
Balance at Sep. 30, 2019	(1,447)	$ 3		(461)	(3,107)	2,118
Balance, shares at Sep. 30, 2019		340,053
Comprehensive income (loss)	1,274			1	1,071	202
Repurchase of common stock	(272)		(95)		(177)
Repurchase of common stock, shares		(2,069)
Share-based benefit plans	96		96
Share-based benefit plans, shares		462
Cash dividends declared	(138)				(138)
Distributions	(138)					(138)
Other	60		(1)			61
Balance at Dec. 31, 2019	(565)	$ 3		(460)	(2,351)	2,243
Balance, shares at Dec. 31, 2019		338,446
Comprehensive income (loss)	587			(111)	581	117
Repurchase of common stock	$ (441)		35		(476)
Repurchase of common stock, shares	(3,287)	(3,287)
Share-based benefit plans	$ (33)		(33)
Share-based benefit plans, shares		2,449
Cash dividends declared	(148)				(148)
Distributions	(154)					(154)
Other	51		(2)			53
Balance at Mar. 31, 2020	(703)	$ 3		(571)	(2,394)	2,259
Balance, shares at Mar. 31, 2020		337,608
Balances at Dec. 31, 2019	(565)	$ 3		(460)	(2,351)	2,243
Balance, shares at Dec. 31, 2019		338,446
Comprehensive income (loss)	2,638
Balance at Sep. 30, 2020	1,299	$ 3	185	(515)	(647)	2,273
Balance, shares at Sep. 30, 2020		338,370
Balances at Mar. 31, 2020	(703)	$ 3		(571)	(2,394)	2,259
Balance, shares at Mar. 31, 2020		337,608
Comprehensive income (loss)	1,225			9	1,079	137
Share-based benefit plans	93		93
Share-based benefit plans, shares		352
Distributions	(45)					(45)
Other	(2)		(5)			3
Balance at Jun. 30, 2020	568	$ 3	88	(562)	(1,315)	2,354
Balance, shares at Jun. 30, 2020		337,960
Comprehensive income (loss)	826			47	668	111
Share-based benefit plans	97		97
Share-based benefit plans, shares		410
Distributions	(194)					(194)
Other	2					2
Balance at Sep. 30, 2020	$ 1,299	$ 3	$ 185	$ (515)	$ (647)	$ 2,273
Balance, shares at Sep. 30, 2020		338,370