Earnings Per Share and Equity (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Earnings Per Share And Equity Additional Narrative Information [Abstract]
Stock options not included in the calculation of diluted common shares outstanding	17,000,000	10,000,000	13,000,000	9,000,000
Treasury Stock, Shares held	35,000,000		35,000,000
Treasury stock, at cost	$ 2,327,000,000		$ 2,327,000,000		$ 2,327,000,000
Earnings Per Share Diluted
Net income on common stock	$ 286,000,000	$ 620,000,000	$ 486,000,000	$ 1,288,000,000
Average common shares outstanding - basic	853,000,000	663,000,000	779,000,000	663,000,000
Assumed exercise of stock options, performance share awards and restricted stock	3,000,000	1,000,000	2,000,000	1,000,000
Average common shares outstanding - diluted	856,000,000	664,000,000	781,000,000	664,000,000