CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Millions	Total	Common Stock [Member]	Treasury Stock [Member]	Capital in Excess of Par Value [Member]	Accumulated Other Comprehensive Income (Loss)	Retained Earnings [Member]	Noncontrolling Interests [Member]
Beginning balance at Dec. 31, 2017	$ 7,627	$ 1	$ (2,818)	$ 6,580	$ 14	$ 2,709	$ 1,141
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	2,951					2,413	538
Currency translation adjustment	(58)				(54)		(4)
Exercise of stock options	79		(4)	74			9
Stock-based compensation	30			26			4
Repurchase of common stock	(905)		(905)
Dividends declared and noncontrolling interest payments	(2,979)					(2,352)	(627)
Ending balance at Dec. 31, 2018	6,745	1	(3,727)	6,680	(40)	2,770	1,061
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	3,304					2,698	606
Currency translation adjustment	42				37		5
Exercise of stock options	54			43			11
Stock-based compensation	35			31			4
Disposition of interest in majority-owned subsidiary, net of taxes	81			(185)			266
Repurchase of common stock	(754)		(754)
Dividends declared and noncontrolling interest payments	(3,000)					(2,367)	(633)
Ending balance at Dec. 31, 2019	6,507	1	(4,481)	6,569	(3)	3,101	1,320
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(2,143)					(1,685)	(458)
Currency translation adjustment	37				32		5
Exercise of stock options	24			22			2
Stock-based compensation	23			19			4
Other	1			1
Dividends declared and noncontrolling interest payments	(911)					(603)	(308)
Ending balance at Dec. 31, 2020	$ 3,538	$ 1	$ (4,481)	$ 6,611	$ 29	$ 813	$ 565