Share Repurchase Program (Narrative) (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	0 Months Ended		12 Months Ended		0 Months Ended	2 Months Ended	50 Months Ended
	Aug. 13, 2014	Feb. 05, 2014	Dec. 31, 2014	Dec. 31, 2013	Feb. 04, 2015	Feb. 27, 2015	Feb. 27, 2015
Proceeds from (Repurchase of) Equity
Increase in authorized amount	$ 500,000,000	$ 500,000,000
Authorization effective period	3 years	3 years
Common stock repurchased, shares			5,743	8,529
Common stock repurchased, average price per share			$ 150.86	$ 109.38
Common stock repurchased, value			866,398,000	932,900,000
Remaining balance under share repurchase program			279,300,000
Subsequent Event [Member]
Proceeds from (Repurchase of) Equity
Increase in authorized amount					500,000,000
Cumulative authorized amount					5,000,000,000
Authorization effective period					3 years
Common stock repurchased, shares						100	46,500
Common stock repurchased, average price per share						$ 197.48	$ 91.38
Common stock repurchased, value						27,800,000	4,200,000,000
Remaining balance under share repurchase program						$ 751,500,000	$ 751,500,000