Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Condensed Consolidated Statements of Operations and Comprehensive Loss
Net sales		$ 59	$ 59	$ 118
Operating expenses
Selling, general and administrative	$ 1,725	2,361	6,259	6,965
Research and development	4,548	3,808	13,404	12,284
Total operating expenses	6,273	6,169	19,663	19,249
Loss from operations	(6,273)	(6,110)	(19,604)	(19,131)
Other income (expense), net	(282)	(22)	(499)	22
Loss before income taxes	(6,555)	(6,132)	(20,103)	(19,109)
Income tax (benefit) expense	3		(124)	(265)
Net loss	$ (6,558)	$ (6,132)	$ (19,979)	$ (18,844)
Basic and diluted loss per share (in dollars per share)	$ (0.36)	$ (0.36)	$ (1.11)	$ (1.12)
Weighted average shares outstanding - basic and diluted (in shares)	18,330	16,903	18,045	16,881
Other comprehensive income:
Foreign currency translation adjustments	$ (16)	$ 17	$ (22)	$ (5)
Total comprehensive loss	$ (6,574)	$ (6,115)	$ (20,001)	$ (18,849)