Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Basic EPS
Income (loss) from continuing operations	$ (2,606)	$ 998	$ (2,641)	$ 3,296
Less: Income from continuing operations attributable to noncontrolling interest		(3)		(8)
Income from continuing operations attributable to common stock	(2,606)	995	(2,641)	3,288
Discontinued operations, net	(3)	213	(10)	741
NET INCOME (LOSS) ATTRIBUTABLE TO COMMON STOCK	(2,609)	1,208	(2,651)	4,029
Less: Net income allocated to participating securities		(3)		(8)
Net income attributable to common stock, net of participating securities	$ (2,609)	$ 1,205	$ (2,651)	$ 4,021
Weighted average number of basic shares	763.3	777.4	766.4	783.7
Basic EPS (in dollars per share)	$ (3.42)	$ 1.55	$ (3.46)	$ 5.13
Diluted EPS
Net income attributable to common stock, net of participating securities	$ (2,609)	$ 1,205	$ (2,651)	$ 4,021
Weighted average number of basic shares	763.3	777.4	766.4	783.7
Dilutive effect of potentially dilutive securities (in shares)		0.3		0.4
Total diluted weighted average common shares	763.3	777.7	766.4	784.1
Diluted EPS (in dollars per share)	$ (3.42)	$ 1.55	$ (3.46)	$ 5.13