Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue:
Product	$ 115,490	$ 120,532	$ 99,259
Research services	2,248	1,986	3,140
Total revenue	117,738	122,518	102,399
Cost of revenue:
Product	93,123	96,865	83,677
Research services	1,304	1,005	1,642
Gross profit	23,311	24,648	17,080
Operating expenses:
Research and development	5,306	5,253	5,980
Sales and marketing	11,810	10,562	10,290
General and administrative	17,415	15,068	16,853
Total operating expenses	34,531	30,883	33,123
Loss from operations	(11,220)	(6,235)	(16,043)
Other expense, net:
Financing costs	(656)		(47)
Interest expense, net	(147)	(182)	(50,281)
Total other expense, net	(803)	(182)	(50,281)
Net loss	$ (12,023)	$ (6,417)	$ (66,324)
Net loss per share:
Basic and diluted	$ (0.52)	$ (0.28)	$ (5.37)
Weighted-average common shares outstanding:
Basic and diluted	23,139,807	22,986,931	12,349,456