Condensed Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenues:
Product	$ 1,265	$ 662	$ 8,333	$ 4,039
License	81	76	243	207
Total revenues	1,346	738	8,576	4,246
Cost of product revenues	1,077	521	6,270	2,065
Gross profit	269	217	2,306	2,181
Operating expenses:
Research and development	4,454	3,350	11,678	8,498
Selling, general and administrative	4,493	2,617	10,447	7,105
Total operating expenses	8,947	5,967	22,125	15,603
Loss from operations	(8,678)	(5,750)	(19,819)	(13,422)
Other income (expense):
Interest income	24	10	25	16
Interest expense	(1,119)	(593)	(5,389)	(1,250)
Change in estimated fair value of financial instruments	3,730	(7,473)	6,717	(7,053)
Gain on extinguishment of debt			49
Other (expense) income, net	(67)	4	(81)	11
Total other income (expense), net	2,568	(8,052)	1,321	(8,276)
Loss before income taxes	(6,110)	(13,802)	(18,498)	(21,698)
Income taxes
Net loss	(6,110)	(13,802)	(18,498)	(21,698)
Deemed dividend on convertible notes			(1,378)	(1,253)
Net loss attributable to common stockholders	$ (6,110)	$ (13,802)	$ (19,876)	$ (22,951)
Net loss per common share:
Basic	$ (0.47)	$ (10.94)	$ (3.83)	$ (18.32)
Diluted	$ (0.53)	$ (10.94)	$ (3.86)	$ (18.32)
Weighted-average shares outstanding used in computing net loss per common share:
Basic	12,888	1,262	5,187	1,253
Diluted	14,017	1,262	5,229	1,253