Earnings Per Share (Details) (USD $) In Millions, except Per Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Basic EPS
Income from continuing operations	$ 1,819	$ 1,089	$ 3,224	$ 2,210
Less: Net income attributable to noncontrolling interest		(12)		(36)
Income from continuing operations attributable to common stock	1,819	1,077	3,224	2,174
Discontinued operations, net	(2)	(14)	142	(47)
Net income attributable to common stock	1,817	1,063	3,366	2,127
Less: Net income allocated to participating securities	(3)	(1)	(6)	(3)
Net income attributable to common stock, net of participating securities	1,814	1,062	3,360	2,124
Weighted average number of basic shares (in shares)	812.5	812.6	812.5	812.3
Basic EPS (in dollars per share)	$ 2.23	$ 1.31	$ 4.14	$ 2.61
Diluted EPS
Net income attributable to common stock, net of participating securities	$ 1,814	$ 1,062	$ 3,360	$ 2,124
Weighted average number of basic shares (in shares)	812.5	812.6	812.5	812.3
Dilutive effect of potentially dilutive securities (in shares)	0.8	1.2	0.8	1.4
Total diluted weighted average common shares (in shares)	813.3	813.8	813.3	813.7
Diluted EPS (in dollars per share)	$ 2.23	$ 1.31	$ 4.13	$ 2.61