Consolidated Statement Of Equity - 3 months ended Mar. 31, 2018 - USD ($) shares in Thousands, $ in Millions	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Retained Earnings	Noncontrolling Interests
Beginning Balance, shares at Dec. 31, 2017		170,189
Beginning Balance at Dec. 31, 2017	$ 11,279	$ 2	$ 8,974	$ (249)	$ 2,547	$ 5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared ($0.16 per share)	(27)				(27)
Purchases of treasury stock, shares		(262)
Purchases of treasury stock	(45)			(45)
Compensation costs:
Vested compensation awards, shares		492
Vested compensation awards	0	$ 0	0
Compensation costs included in net income	17		17			0
Net income	178				178	0
Ending Balance, shares at Mar. 31, 2018		170,419
Ending Balance at Mar. 31, 2018	$ 11,402	$ 2	$ 8,991	$ (294)	$ 2,698	$ 5