Consolidated Statements of Changes in Stockholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Common stock	Additional Paid-in Capital	Accumulated Deficit	Treasury stock
Balances at Dec. 31, 2010	$ 30,658	$ 2	$ 349,747	$ (242,327)	$ (76,764)
Balances (in shares) at Dec. 31, 2010		25,877			2,862
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(19,438)			(19,438)
Stock-based compensation to employees and directors	3,051		3,051
Common stock issued upon vesting of restricted stock (in shares)		318
Purchase of treasury stock	(1,604)				(1,604)
Purchase of treasury stock (in shares)					100
Lapse of rescission rights of redeemable common stock	582		582
Lapse of rescission rights of redeemable common stock (in shares)		46
Deemed dividend related to redeemable common stock	(12)		(12)
Balances at Dec. 31, 2011	13,237	2	353,368	(261,765)	(78,368)
Balances (in shares) at Dec. 31, 2011		26,241			2,962
Increase (Decrease) in Stockholders' Equity
Net income (loss)	14,669			14,669
Stock-based compensation to employees and directors	3,527		3,527
Common stock issued upon vesting of restricted stock (in shares)		240
Purchase of treasury stock	(471)				(471)
Purchase of treasury stock (in shares)					68
Lapse of rescission rights of redeemable common stock	0
Deemed dividend related to redeemable common stock	0
Balances at Dec. 31, 2012	30,962	2	356,895	(247,096)	(78,839)
Balances (in shares) at Dec. 31, 2012		26,481			3,030
Increase (Decrease) in Stockholders' Equity
Net income (loss)	88,509			88,509
Stock-based compensation to employees and directors	3,251		3,251
Common stock issued upon vesting of restricted stock (in shares)		339
Exercise of stock options	1,560		1,560
Exercise of stock options (in shares)		89
Purchase of treasury stock	(1,391)				(1,391)
Purchase of treasury stock (in shares)					94
Lapse of rescission rights of redeemable common stock	0
Deemed dividend related to redeemable common stock	0
Balances at Dec. 31, 2013	$ 122,891	$ 2	$ 361,706	$ (158,587)	$ (80,230)
Balances (in shares) at Dec. 31, 2013		26,909			3,124