Consolidated Statement Of Equity - 6 months ended Jun. 30, 2017 - USD ($) shares in Thousands, $ in Millions	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Noncontrolling Interests [Member]
Beginning Balance, shares at Dec. 31, 2016		169,724
Beginning Balance at Dec. 31, 2016	$ 10,411	$ 2	$ 8,892	$ (218)	$ 1,728	$ 7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared ($0.04 per share)	(7)				(7)
Treasury stock purchases, shares		(188)
Treasury stock purchases	(36)			(36)
Compensation costs:
Vested compensation awards, shares		561
Vested compensation awards	0	$ 0	0
Compensation costs included in net income	43		43			0
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	0		2			(2)
Net Income (Loss) Attributable to Parent					191
Net loss	191					0
Ending Balance, shares at Jun. 30, 2017		170,097
Ending Balance at Jun. 30, 2017	$ 10,602	$ 2	$ 8,937	$ (254)	$ 1,912	$ 5