Consolidated Statement of Equity (Unaudited) - 6 months ended Jun. 30, 2018 - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Capital in Excess of Par Value	Accumulated Deficit	Accumulated Other Comprehensive Loss	Common Stock Held in Treasury	Total Stockholder's Equity	Noncontrolling Interests
Balance (in shares) at Dec. 31, 2017		1,578				130
Balance at Dec. 31, 2017	$ 11,296	$ 158	$ 26,751	$ (14,722)	$ (487)	$ (3,723)	$ 7,977	$ 3,319
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercised and issued stock-based awards (in shares)		1				0
Exercised and vested stock-based awards	8	$ 0	8	0	0	$ 0	8	0
Stock-based compensation, including the tender of shares	50	0	53	0	0	$ (3)	50	0
Stock-based compensation, including the tender of shares (in shares)						0
Dividends	(386)	0	(145)		0	$ 0	(145)	(241)
Net income attributable to common stockholders	1,561	0		1,561		0	1,561	0
Net income attributable to noncontrolling interests	291	0				0	0	291
Other comprehensive income (loss)	22	$ 0	0		23	$ 0	23	(1)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	1,874
Balance (in shares) at Jun. 30, 2018		1,579				130
Balance at Jun. 30, 2018	$ 12,842	$ 158	$ 26,667	$ (13,161)	$ (464)	$ (3,726)	$ 9,474	$ 3,368