Stock-Based Compensation Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Cash received from option exercises	$ 332	$ 4,279	$ 12,808
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding, beginning of period	2,695,276	2,659,884	3,195,573
Options granted	31,500	462,250	61,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 16.71	$ 22.99	$ 31.38
Options exercised	(21,730)	(274,551)	(560,808)
Options exercised, weighted average exercise price (in dollars per share)	$ 15.29	$ 15.46	$ 22.78
Options forfeited and expired	(309,939)	(152,307)	(35,881)
Options, forfeited and expired, weighted average exercise price (in dollars per share)	$ 23.63	$ 26.23	$ 32.58
Options outstanding, end of period	2,395,107	2,695,276	2,659,884
Options outstanding, weighted average exercise price	$ 24.13	$ 24.09	$ 23.51	$ 23.33
Options outstanding, weighted average remaining contractual term	6 years
Options outstanding, intrinsic value	$ 2,827
Options exercisable	1,389,060
Options exercisable, weighted average exercise price (in dollars per share)	$ 23.71
Options exercisable, weighted average remaining contractual term (in years)	5 years 7 months 28 days
Options exercisable, intrinsic value	$ 2,035
Options, vested and expected to vest, net of anticipated forfeitures	2,307,140
Options, vested and expected to vest, net of anticipated forfeitures, weighted average exercise price (in dollars per share)	$ 24.07
Options, vested and expected to vest, net of anticipated forfeitures, weighted average remaining contractual term (in years)	5 years 11 months 27 days
Options, vested and expected to vest, net of anticipated forfeitures, aggregate intrinsic value	$ 2,771
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	$ 100	$ 1,800	$ 9,600