Earnings Per Share, Share Repurchases and Dividends on Common Stock #2 (Details) (USD $)	1 Months Ended			3 Months Ended		6 Months Ended
	May 31, 2013	May 31, 2012	May 31, 2011	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share, Basic and Diluted [Abstract]
Dilutive effect of of stock awards granted to employees under stock-based compensation plans				3,500,000	3,900,000	4,000,000	4,500,000
Anti-dilutive shares excluded from computation of earnings per share				0	2,800,000	700,000	2,800,000
Common stock dividends per share, declared (in dollars per share)	$ 0.61	$ 0.55	$ 0.50			$ 1.16	$ 1.05
Increase in quarterly common stock dividend (percent)				11.00%	10.00%