Unaudited Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Unaudited Condensed Consolidated Statements of Operations and Comprehensive Income (Loss)
Revenue	$ 553
Cost of sales	1,045
Gross profit	(492)
Expenses:
Sales and marketing expenses	1,140	$ 633
Research and development expenses	6,998	6,416
General and administrative expenses	3,767	3,879
Operating loss	(12,397)	(10,928)
Other income (expense), net:
Interest income	21	2
Interest expense	(684)	(276)
Other expense	(13)	(14)
Net loss	(13,073)	(11,216)
Total comprehensive loss	$ (13,073)	$ (11,216)
Basic and diluted net loss per common share	$ (0.14)	$ (0.15)
Basic and diluted weighted-average shares outstanding (in shares)	93,905,880	77,324,890