Earnings Per Share (Narrative) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		1 Months Ended	40 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	May 09, 2014 Subsequent Event [Member]	May 09, 2014 Subsequent Event [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Common stock repurchased, shares	149	2,468	300	41,100
Common stock repurchased, average price per share	$ 148.18	$ 92.35	$ 145.55	$ 83.35
Common stock repurchased, value	$ 22,065	$ 227,893	$ 48,500	$ 3,400,000