Share Repurchase Program (Narrative) (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	0 Months Ended	1 Months Ended	3 Months Ended		6 Months Ended		18 Months Ended	19 Months Ended
	Jun. 01, 2012	Aug. 08, 2012	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Aug. 08, 2012
Share Repurchase Program
Increase in authorized amount	$ 500,000,000
Cumulative authorized amount	2,000,000,000
Authorization effective period	3 years
Remaining balance under share repurchase program							429,300,000
Common stock repurchased, shares		3,340	4,518	3,301	6,288	5,912		25,500
Common stock repurchased, average price per share		$ 85.49	$ 97.47	$ 58.44	$ 94.52	$ 57.16		$ 72.78
Common stock repurchased, value		$ 285,521,000	$ 440,369,000	$ 192,901,000	$ 594,355,000	$ 337,912,000		$ 1,900,000,000