Earnings Per Share (Details Textuals) (USD $) Share data in Millions, except Per Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Earnings Per Share (Textuals)
Options to purchase shares of common stock not included in the computation of diluted earnings per share	13.8	14.4	12.7	13.5
Repurchased shares of common stock	10.1		16.2
Average price per share	$ 54.30		$ 56.05
Total cash outlay	$ 549,300,000		$ 906,500,000
Amount remains authorized for future repurchases			300,000,000
Amount authorized for share repurchase program			$ 1,500,000,000