Stock-Based Employee Compensation (Options Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Number of Options
Outstanding at January 1, 2016 (Options)	411,809
Granted (Options)	0
Exercised (Options)	(61,014)
Canceled (Options)	(4,485)
Outstanding at December 31, 2016 (Options)	346,310	411,809
Vested and expected to vest at December 31, 2016 (Options)	346,310
Options Exercisable at December 31, 2016 (Options)	346,310
Weighted-Average Exercise Price
Outstanding at January 1, 2016 (Price per Share)	$ 33.69
Granted (Price per Share)	0.00
Exercised (Price per Share)	37.87
Canceled (Price per Share)	44.72
Outstanding at December 31, 2016 (Price per Share)	32.82	$ 33.69
Vested and expected to vest at December 31, 2016 (Price per Share)	32.82
Options Exercisable at December 31, 2016 (Price per Share)	$ 32.82
Weighted-Average Remaining Contractual Term
Outstanding at January 1, 2016 (Years)	2 years 3 months 50 days	3 years 1 month 15 days
Outstanding at December 31, 2016 (Years)	2 years 3 months 50 days	3 years 1 month 15 days
Vested and expected to vest at December 31, 2016 (Years)	2 years 3 months 50 days
Options Exercisable at December 31, 2016 (Years)	2 years 3 months 50 days
Aggregate Intrinsic Value
Outstanding at January 1, 2016	$ 17,221	$ 28,111
Outstanding at December 31, 2016	17,221	28,111
Vested and expected to vest at December 31, 2016	17,221
Options Exercisable at December 31, 2016	17,221
Total intrinsic value of stock options exercised	$ 17,200	$ 13,800	$ 35,900