Earnings Per Share (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended		58 Months Ended
	Nov. 06, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Nov. 06, 2015
Earnings Per Share
Common stock repurchased, shares		1,147	2,542	3,784	4,564
Common stock repurchased, average price per share		$ 238.97	$ 152.42	$ 224.39	$ 150.55
Common stock repurchased, value		$ 274,213	$ 387,461	$ 849,145	$ 687,086
Subsequent event [Member]
Earnings Per Share
Common stock repurchased, shares	100					50,300
Common stock repurchased, average price per share	$ 249.06					$ 101.51
Common stock repurchased, value	$ 32,300					$ 5,100,000