Stock Repurchase Programs (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	1 Months Ended	3 Months Ended	9 Months Ended	1 Months Ended	9 Months Ended		1 Months Ended	9 Months Ended
	Mar. 31, 2013 March 2013 Stock Plan	Nov. 02, 2013 March 2013 Stock Plan	Nov. 02, 2013 March 2013 Stock Plan	Feb. 29, 2012 2012 Stock Plan	Nov. 02, 2013 2012 Stock Plan	Oct. 27, 2012 2012 Stock Plan	May 31, 2011 May 2011 Stock Plan	Oct. 27, 2012 May 2011 Stock Plan
Stock Repurchase Programs
Stock repurchase authorization	$ 250,000,000			$ 250,000,000			$ 250,000,000
Number of shares repurchased		2,400	2,700		1,200	2,100		439
Amount of shares repurchased		186,900,000	209,600,000		92,000,000	134,600,000		27,500,000
Average price of shares repurchased (in dollars per share)		$ 77.80	$ 77.93		$ 79.14	$ 64.52		$ 62.71
Repurchase of common stock remaining authorization			$ 40,400,000