Statement of Consolidated Changes in Equity (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]	Series D Preferred Stock [Member]
BALANCE at Dec. 31, 2011	$ 28,993	$ 241	$ 9,066	$ 18,500	$ (32)	$ (9)	$ 28,993		$ 1,227
Net income	2,001			2,001			2,001
Postretirement, net of tax of $5	(2)					(2)	(2)
Commodity hedges, net of tax	(120)					(120)	(120)
Preferred	(76)			(76)			(76)
Common ($0.68 per share)	(264)			(264)			(264)
Common shares issued	601	3	598				601
Common stock activity, net	(43)	1	(44)				(43)
Treasury stock activity, net	3		1		2		3
Compensation expense	238		238				238
BALANCE at Dec. 31, 2012	31,331	245	9,859	20,161	(30)	(131)	31,331		1,227
Net income	2,288			2,232			2,232	56
Postretirement, net of tax of $5	9					9	9
Commodity hedges, net of tax	7					7	7
Preferred	(44)			(44)			(44)
Common ($0.68 per share)	(317)			(317)			(317)
Common stock activity, net	(21)	1	(22)				(21)
Treasury stock activity, net	(997)				(997)		(997)
Sale of noncontrolling interest	2,948		1,007				1,007	1,941
Conversion of Series D preferred stock		9	1,218						(1,227)
Compensation expense	189		189				189
BALANCE at Dec. 31, 2013	35,393	255	12,251	22,032	(1,027)	(115)	33,396	1,997
Net income	(5,060)			(5,403)			(5,403)	343
Distributions to noncontrolling interest	(140)							(140)
Commodity hedges, net of tax	(1)					(1)	(1)
Common ($0.68 per share)	(380)			(380)			(380)
Common stock activity, net	(10)	1	(11)				(10)
Treasury stock activity, net	(1,864)		(1)		(1,863)		(1,864)
Compensation expense	202		202				202
Other	(3)		(3)				(3)
BALANCE at Dec. 31, 2014	$ 28,137	$ 256	$ 12,438	$ 16,249	$ (2,890)	$ (116)	$ 25,937	$ 2,200