Earnings Per Share (Narrative) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended		2 Months Ended	50 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Feb. 27, 2015	Feb. 27, 2015
Proceeds from (Repurchase of) Equity
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	$ 932,900
Subsequent Event [Member]
Proceeds from (Repurchase of) Equity
Common stock repurchased, shares			100	46,500
Common stock repurchased, average price per share			$ 197.48	$ 91.38
Common stock repurchased, value			$ 27,800	$ 4,200,000