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, 2009	$ 10,800	$ 2	$ 343,040	$ (256,056)	$ (76,186)
Treasury stock balances (in shares) at Dec. 31, 2009					2,807
Balances (in shares) at Dec. 31, 2009		25,583
Increase (Decrease) in Stockholders' Equity
Net income (loss)	13,889			13,889
Exercise of stock options	1,503		1,503
Exercise of stock options (in shares)		90
Stock-based compensation to employees and directors	5,056		5,056
Common stock issued upon vesting of restricted stock (in shares)		185
Purchase of treasury stock	(825)				(825)
Purchase of treasury stock (in shares)					63
Lapse of rescission rights of redeemable common stock	260		260
Lapse of rescission rights of redeemable common stock (in shares)		18
Treasury stock issued for 401(k) matching contributions	87			(160)	247
Treasury stock issued for 401(k) matching contributions (in shares)					(7)
Redeemable common stock repurchased under rescission offer (in shares)		1			(1)
Deemed dividend related to redeemable common stock	(112)		(112)
Balances at Dec. 31, 2010	30,658	2	349,747	(242,327)	(76,764)
Treasury stock balances (in shares) at Dec. 31, 2010					2,862
Balances (in shares) at Dec. 31, 2010		25,877
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)
Treasury stock balances (in shares) at Dec. 31, 2011	2,962				2,962
Balances (in shares) at Dec. 31, 2011		26,241
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
Balances at Dec. 31, 2012	$ 30,962	$ 2	$ 356,895	$ (247,096)	$ (78,839)
Treasury stock balances (in shares) at Dec. 31, 2012	3,030				3,030
Balances (in shares) at Dec. 31, 2012		26,481