Consolidated Statements of Stockholders' Equity (USD $) In Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning Balance at Dec. 31, 2010	$ 185,403	$ 32	$ 424,270	$ (25,000)	$ (213,920)	$ 21
Beginning Balance, shares at Dec. 31, 2010		31,852
Exercise of stock options, vesting of restricted stock units and shares issued under employee stock purchase plan	504	0	504	0	0	0
Exercise of stock options, vesting of restricted stock units and shares issued under employee stock purchase plan, shares		410
Taxes withheld on net settled vesting of restricted stock units	(700)	0	(700)	0	0	0
Net tax effect from stock options exercised	(244)	0	(244)	0	0	0
Share-based compensation	5,983	0	5,983	0	0	0
Net loss	(24,892)	0	0	0	(24,892)	0
Other comprehensive income (loss)	(29)	0	0	0	0	(29)
Ending Balance at Dec. 31, 2011	166,025	32	429,813	(25,000)	(238,812)	(8)
Ending Balance, shares at Dec. 31, 2011		32,262
Exercise of stock options, vesting of restricted stock units and shares issued under employee stock purchase plan	1,599	2	1,597	0	0	0
Exercise of stock options, vesting of restricted stock units and shares issued under employee stock purchase plan, shares		1,393
Taxes withheld on net settled vesting of restricted stock units	(433)	0	(433)	0	0	0
Share-based compensation	7,500	0	7,500	0	0	0
Net loss	(89,266)	0	0	0	(89,266)	0
Other comprehensive income (loss)	22	0	0	0	0	22
Ending Balance at Dec. 31, 2012	85,447	34	438,477	(25,000)	(328,078)	14
Ending Balance, shares at Dec. 31, 2012		33,655
Exercise of stock options, vesting of restricted stock units and shares issued under employee stock purchase plan	102	0	102	0	0	0
Exercise of stock options, vesting of restricted stock units and shares issued under employee stock purchase plan, shares		442
Taxes withheld on net settled vesting of restricted stock units	(654)	0	(654)	0	0	0
Share-based compensation	3,443	0	3,443	0	0	0
Net loss	(43,413)	0	0	0	(43,413)	0
Other comprehensive income (loss)	(9)	0	0	0	0	(9)
Ending Balance at Dec. 31, 2013	$ 44,916	$ 34	$ 441,368	$ (25,000)	$ (371,491)	$ 5
Ending Balance, shares at Dec. 31, 2013		34,097