Condensed Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Millions	Total	Common Stock [Member]	Capital in Excess of Par Value [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings (Deficit) [Member]	Equity Attributable to Noncontrolling Interests [Member]
Balances at Dec. 31, 2019	$ (565)	$ 3		$ (460)	$ (2,351)	$ 2,243
Balance, shares at Dec. 31, 2019		338,446,000
Comprehensive income (loss)	587			(111)	581	117
Repurchase of common stock	(441)				(441)
Repurchase of common stock, shares		(3,287,000)
Share-based benefit plans	(33)		$ 2		(35)
Share-based benefit plans, shares		2,449,000
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		337,608,000
Comprehensive income (loss)	1,225			9	1,079	137
Share-based benefit plans	93		93
Share-based benefit plans, shares		352,000
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		337,960,000
Comprehensive income (loss)	826			47	668	111
Share-based benefit plans	97		97
Share-based benefit plans, shares		410,000
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		338,370,000
Comprehensive income (loss)	1,707			13	1,426	268
Share-based benefit plans	108		108
Share-based benefit plans, shares		1,056,000.000
Cash dividends declared	(2)				(2)
Distributions	(233)					(233)
Other	13		1			12
Balance at Dec. 31, 2020	2,892	$ 3	294	(502)	777	2,320
Balance, shares at Dec. 31, 2020		339,426,000
Comprehensive income (loss)	1,591			11	1,423	157
Repurchase of common stock	$ (1,527)		(225)		(1,302)
Repurchase of common stock, shares	(8,477,000)	(8,477,000)
Share-based benefit plans	$ (75)		(75)
Share-based benefit plans, shares		2,765,000
Cash dividends declared	(163)				(163)
Distributions	(234)					(234)
Other	(2)		$ 6			(8)
Balance at Mar. 31, 2021	$ 2,482	$ 3		$ (491)	$ 735	$ 2,235
Balance, shares at Mar. 31, 2021		333,714,000