STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Net sales	$ 530	$ 163
Cost of sales	26	0
Gross Profit	504	163
Costs and expenses:
Research and development	4,288	7,675
Sales, general and administrative	10,526	7,660
Total costs and expenses	14,814	15,335
Loss from operations	(14,310)	(15,172)
Foreign currency exchange gain (loss)	(26)	44
Interest and dividend income	136	54
Total other income	110	98
Net loss	$ (14,200)	$ (15,074)
Basic and diluted net loss per share (dollars per share)	$ (0.27)	$ (0.29)
Weighted average shares outstanding (shares)	51,887	51,196
Other comprehensive loss:
Net loss	$ (14,200)	$ (15,074)
Net unrealized gain on available-for-sale investments	11	52
Foreign currency translation adjustment	56	(49)
Comprehensive loss	$ (14,133)	$ (15,071)