CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Common Stock [Member] USD ($)	Common Stock [Member] Issued at $3.93-3.59 per share [Member]	Additional Paid-in Capital [Member] USD ($)	Additional Paid-in Capital [Member] Issued at $3.93-3.59 per share [Member] USD ($)	Accumulated Deficit [Member] USD ($)	Other Comprehensive Income (Expense) [Member] USD ($)	Total USD ($)	Issued at $3.93-3.59 per share [Member] USD ($)
Balance at Dec. 31, 2010	$ 5		$ 78,187		$ (17,755)	$ (984)	$ 59,453
Balance (in shares) at Dec. 31, 2010	49,341,028
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued for cash exercise of warrants, net				3,063				3,063
Stock issued for cash exercise of warrants (in shares)		855,536
Stock-based compensation			4,368				4,368
Deferred tax benefit related to stock based compensation			2,331				2,331
Derivative liability			15,260				15,260
Cashless exercise of underwriter warrants							0
Cashless exercise of underwriter warrants (in shares)	24,178
Exercise of options			1,068				1,068
Exercise of options (in shares)	398,394
Comprehensive income:
Reclassification adjustment for net loss included in net income					(983)	983	0
Net loss					(17,263)		(17,263)
Other comprehensive income net of tax						(3)	(3)
Comprehensive loss							(17,266)
Balance at Dec. 31, 2011	5		104,277		(36,001)	(4)	68,277
Balance (in shares) at Dec. 31, 2011	50,619,136
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued for cash exercise of warrants, net				161				161
Stock issued for cash exercise of warrants (in shares)		44,941
Stock-based compensation			6,162				6,162
Deferred tax benefit related to stock based compensation			3,111				3,111
Derivative liability			1,454				1,454
Exercise of options			1,691				1,691
Exercise of options (in shares)	486,165
Comprehensive income:
Net loss					(26,924)		(26,924)
Other comprehensive income net of tax						12	12
Comprehensive loss							(26,912)
Balance at Dec. 31, 2012	5		116,856		(62,925)	8	53,944
Balance (in shares) at Dec. 31, 2012	51,150,242
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation			7,563				7,563
Exercise of options			170				170
Exercise of options (in shares)	39,833
Vested RSU's (in shares)	46,066
Comprehensive income:
Net loss					(27,608)		(27,608)
Other comprehensive income net of tax						(45)	(45)
Comprehensive loss							(27,653)
Balance at Dec. 31, 2013	$ 5		$ 124,589		$ (90,533)	$ (37)	$ 34,024
Balance (in shares) at Dec. 31, 2013	51,236,141