Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Net revenue	$ 1,754	$ 257
Cost of goods sold	2,356	2,030
Gross loss	(602)	(1,773)
Operating expenses:
Research and development	1,450	2,058
Selling, general and administrative	3,984	3,491
Total operating expenses	5,434	5,549
Operating loss	(6,035)	(7,322)
Other expense (income):
Interest expense	460	47
Other expense (income), net	(52)	(71)
Total other expense (income), net	408	(24)
Operating loss before income tax provision	(6,443)	(7,298)
Provision for income taxes
Net loss	$ (6,443)	$ (7,298)
Net loss per common share: basic and diluted (in dollars per share)	$ (0.07)	$ (0.08)
Weighted-average number of common shares used in computing net loss per common share: basic and diluted (in shares)	95,943	87,432
Comprehensive Loss:
Net loss	$ (6,443)	$ (7,298)
Unrealized loss on investments	(9)
Total comprehensive loss	$ (6,440)	$ (7,298)