Stock-Based Employee Compensation (Options Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Number of Options
Outstanding at January 1, 2015 (Options)	706,051
Granted (Options)	0
Exercised (Options)	(287,379)
Canceled (Options)	(6,863)
Outstanding at December 31, 2015 (Options)	411,809	706,051
Vested and expected to vest at December 31, 2015 (Options)	411,807
Options Exercisable at December 31, 2015 (Options)	409,915
Weighted-Average Exercise Price
Outstanding at January 1, 2015 (Price per Share)	$ 36.03
Granted (Price per Share)	0.00
Exercised (Price per Share)	39.12
Canceled (Price per Share)	47.05
Outstanding at December 31, 2015 (Price per Share)	33.69	$ 36.03
Vested and expected to vest at December 31, 2015 (Price per Share)	33.69
Options Exercisable at December 31, 2015 (Price per Share)	$ 33.73
Weighted-Average Remaining Contractual Term
Outstanding at January 1, 2015 (Years)	3 years 1 month 12 days	3 years 7 months 21 days
Outstanding at December 31, 2015 (Years)	3 years 1 month 12 days	3 years 7 months 21 days
Vested and expected to vest at December 31, 2015 (Years)	3 years 1 month 12 days
Options Exercisable at December 31, 2015 (Years)	3 years 1 month 11 days
Aggregate Intrinsic Value
Outstanding at January 1, 2015	$ 33,182
Outstanding at December 31, 2015	28,111	$ 33,182
Vested and expected to vest at December 31, 2015	28,110
Options Exercisable at December 31, 2015	27,967
Total intrinsic value of stock options exercised	$ 13,800	$ 35,900	$ 17,500
Stock Option
Aggregate Intrinsic Value
Weighted-average period of unrecognized compensation cost to be recognized (Years)	5 days