Net Income (Loss) Per Common Share - Reconciliation of the Numerators and Denominators of Basic and Diluted Net Income (Loss) Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Net income (loss) used to compute net income (loss) per common share:
Basic	$ (6,016)	$ 1,168	$ (9,279)	$ (7,988)
Adjustment for change in fair value of liability classified stock options	(58)	(2,244)	(100)
Diluted	$ (6,074)	$ (1,076)	$ (9,379)	$ (7,988)
Weighted average number of common shares:
Basic	14,408,108	14,241,827	14,401,054	14,227,203
Adjustment for dilutive effect of stock options	26,494	888,151	27,106
Diluted	14,434,602	15,129,978	14,428,160	14,227,203
Net income (loss) per common share - basic	$ (0.42)	$ 0.08	$ (0.64)	$ (0.56)
Net loss per common share - diluted	$ (0.42)	$ (0.07)	$ (0.65)	$ (0.56)