CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenue	$ 34,223	$ 36,416	$ 39,657
Cost of revenue	23,464	21,188	22,602
Gross profit	10,759	15,228	17,055
Operating expenses:
Research and development	25,643	21,800	15,187
Selling, general and administrative	45,989	37,729	29,965
Amortization of intangible assets	202	202	202
Total operating expenses	71,834	59,731	45,354
Loss from operations	(61,075)	(44,503)	(28,299)
Non-operating income (expense), net:
Gain (loss) from revaluation of warrant liability	3,566	7,708	(15,099)
Foreign exchange (loss) gain	(396)	(1,296)	533
Interest expense	(1,705)	(599)	(332)
Other income, net	71	130	78
Total non-operating income (expense), net	1,536	5,943	(14,820)
Loss before income taxes	(59,539)	(38,560)	(43,119)
(Benefit) provision for income taxes	(3,671)	195	218
Net loss	$ (55,868)	$ (38,755)	$ (43,337)
Net loss per share:
Basic	$ (0.58)	$ (0.52)	$ (0.64)
Diluted	$ (0.61)	$ (0.61)	$ (0.64)
Weighted average shares outstanding used for calculating net loss per share:
Basic	96,068	74,767	67,569
Diluted	96,905	76,534	67,569