Consolidated Statements Of Stockholders' Equity (USD $) In Thousands, except Share data	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-In Capital [Member]	Accum Other Comp Inc. [Member]	Accum Deficit [Member]	Total
Balance at Dec. 31, 2008	$ 21	$ (3,084)	$ 260,581	$ 129	$ (149,254)	$ 108,393
Balance, shares at Dec. 31, 2008	21,279,692	(730,733)
Exercise of stock options			420			420
Exercise of stock options, shares	150,621
Stock-based compensation			937			937
Unrealized gain (loss) on investments				(126)		(126)
Foreign currency translation adjustments				(13)		(13)
Net exercise of stock warrants, shares	43,885
Stock issued to board of directors			36			36
Stock issued to board of directors, shares	8,360
Purchase of treasury stock, at cost		(2,577)				(2,577)
Purchase of treasury stock, at cost, shares		(519,242)
Net income (loss)					(9,630)	(9,630)
Comprehensive income (loss)						(9,769)
Balance at Dec. 31, 2009	21	(5,661)	261,974	(10)	(158,884)	97,440
Balance, shares at Dec. 31, 2009	21,482,558	(1,249,975)
Exercise of stock options			1,640			1,640
Exercise of stock options, shares	532,986
Stock-based compensation			2,252			2,252
Unrealized gain (loss) on investments				(9)		(9)
Foreign currency translation adjustments				9		9
Net income (loss)					29,111	29,111
Comprehensive income (loss)						29,111
Proceeds from secondary public offering net of issuance costs	2		61,649			61,651
Proceeds from secondary public offering net of issuance costs, shares	2,195,100
Balance at Dec. 31, 2010	23	(5,661)	327,515	(10)	(129,773)	192,094
Balance, shares at Dec. 31, 2010	24,210,644	(1,249,975)
Exercise of stock options	1		741			742
Exercise of stock options, shares	71,355
Stock-based compensation			2,297			2,297
Unrealized gain (loss) on investments				(42)		(42)
Foreign currency translation adjustments				2		2
Stock issued to board of directors			162			162
Stock issued to board of directors, shares	7,724
Purchase of treasury stock, at cost		(6,487)				(6,487)
Purchase of treasury stock, at cost, shares		(524,869)
Net income (loss)					38,059	38,059
Comprehensive income (loss)						38,019
Excess tax benefit of stock based compensation			1,404			1,404
Balance at Dec. 31, 2011	$ 24	$ (12,148)	$ 332,119	$ (50)	$ (91,714)	$ 228,231
Balance, shares at Dec. 31, 2011	24,289,723	(1,774,844)