CONSOLIDATED STATEMENT OF EQUITY - 9 months ended Sep. 30, 2017 - USD ($) $ in Millions		Total	Common Stock [Member]	Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interests [Member]	Subsidiary Equity Transactions [Member]	Subsidiary Equity Transactions [Member] Paid-in Capital [Member]
Balance at Dec. 31, 2016		$ 15,497	$ 57	$ 11,875	$ 1,704	$ (1,033)	$ (391)	$ 3,285
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		(1,250)			(1,432)			182
Common stock issued	[1]	123	0	123		0
Dividends—common stock		(84)			(84)
Repurchase of common stock		(37)				(37)
Subsidiary equity transactions									$ (23)	$ (23)
Distributions to noncontrolling interest owners		(327)						(327)
Reclassification of previously deferred derivative losses to (gains) losses on derivatives, net		2					2
Adjustments for pension and other postretirement plans		52					52
Balance at Sep. 30, 2017		13,922	$ 57	11,972	160	$ (1,070)	$ (337)	$ 3,140
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting change		$ (31)		$ (3)	$ (28)

[1] Represents share-based compensation expense.