Basis of Presentation (Earnings (Loss) Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Summary of computation of basic and diluted net income (loss) per share
Net income	$ 23,564	$ 1,592	$ 24,318	$ 3,688
Shares used to compute basic income per share	19,725,410	20,738,299	19,668,183	20,668,110
Dilutive potential common shares:
Restricted stock	42,836	29,029	52,187	44,815
Stock options	1,044,926	1,012,706	1,001,147	1,063,200
Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities	463,232	0	231,617	0
Shares used to compute diluted income per share	21,276,404	21,780,034	20,953,134	21,776,125
Basic per share amounts:
Net income (in usd per share)	$ 1.19	$ 0.08	$ 1.24	$ 0.18
Diluted per share amounts:
Net income (in usd per share)	$ 1.11	$ 0.07	$ 1.16	$ 0.17