Statement of Consolidated Changes in Equity (Unaudited) - USD ($) $ in Millions	Total	Common Stock [Member]	Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Parent [Member]	Noncontrolling Interest [Member]
BALANCE at Dec. 31, 2013	$ 35,393	$ 255	$ 12,251	$ 22,032	$ (1,027)	$ (115)	$ 33,396	$ 1,997
Net income (loss)	(294)			(589)			(589)	295
Distributions to noncontrolling interest	(124)							(124)
Commodity hedges, net of tax	(1)					(1)	(1)
Common dividends ($0.75 per share)	(287)			(287)			(287)
Common stock activity, net	(11)	1	(12)				(11)
Treasury stock activity, net	(1,831)		(1)		(1,830)		(1,831)
Compensation expense	145		145				145
Other	(4)		(4)				(4)
BALANCE at Sep. 30, 2014	32,986	256	12,379	21,156	(2,857)	(116)	30,818	2,168
BALANCE at Dec. 31, 2014	28,137	256	12,438	16,249	(2,890)	(116)	25,937	2,200
Net income (loss)	(15,846)			(15,906)			(15,906)	60
Distributions to noncontrolling interest	(97)							(97)
Common dividends ($0.75 per share)	(283)			(283)			(283)
Other	61	1	59		1		61
BALANCE at Sep. 30, 2015	$ 11,972	$ 257	$ 12,497	$ 60	$ (2,889)	$ (116)	$ 9,809	$ 2,163