Condensed Consolidated Statements of Equity (Unaudited) - USD ($) $ in Millions	Total	Common Stock [Member]	Treasury Stock [Member]	Capital in Excess of Par Value [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	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	2,991					2,583	408
Currency translation adjustment	(51)				(50)		(1)
Exercise of stock options	78		(4)	73			9
Stock-based compensation	23			20			3
Repurchase of common stock	(475)		(475)
Dividends declared and noncontrolling interest payments (Note 4)	(2,395)					(1,771)	(624)
Ending balance at Sep. 30, 2018	7,798	1	(3,297)	6,673	(36)	3,521	936
Beginning balance at Jun. 30, 2018	7,962	1	(2,997)	6,660	(44)	3,538	804
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	699					571	128
Currency translation adjustment	12				8		4
Exercise of stock options	9			7			2
Stock-based compensation	7			6			1
Repurchase of common stock	(300)		(300)
Dividends declared and noncontrolling interest payments (Note 4)	(591)					(588)	(3)
Ending balance at Sep. 30, 2018	7,798	1	(3,297)	6,673	(36)	3,521	936
Beginning 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	2,521					2,069	452
Currency translation adjustment	(36)				(34)		(2)
Exercise of stock options	44			35			9
Stock-based compensation	27			24			3
Disposition of interest in majority-owned subsidiary	81			(185)			266
Repurchase of common stock	(454)		(454)
Dividends declared and noncontrolling interest payments (Note 4)	(2,413)					(1,780)	(633)
Ending balance at Sep. 30, 2019	6,515	1	(4,181)	6,554	(74)	3,059	1,156
Beginning balance at Jun. 30, 2019	6,582	1	(4,081)	6,541	(19)	3,118	1,022
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	669					533	136
Currency translation adjustment	(58)				(55)		(3)
Exercise of stock options	5			5
Stock-based compensation	9			8			1
Repurchase of common stock	(100)		(100)
Dividends declared and noncontrolling interest payments (Note 4)	(592)					(592)
Ending balance at Sep. 30, 2019	$ 6,515	$ 1	$ (4,181)	$ 6,554	$ (74)	$ 3,059	$ 1,156