Condensed Consolidated Statements of Operations (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Product revenue	$ 1	$ 2	$ 4	$ 2
Cost of product revenue	42	51	42	69
Gross loss	(41)	(49)	(38)	(67)
Expenses
Research and development	974	658	1,506	1,623
Sales and marketing	0	165	27	360
General and administrative	2,195	1,423	3,214	3,273
Total expenses	3,169	2,246	4,747	5,256
Operating loss	(3,210)	(2,295)	(4,785)	(5,323)
Interest and other income (expense)
Interest Income	3	0	4	0
Change in fair value of warrants liabilities income (expense)	(32)	(56)	(101)	1,095
Cease-use expense	0	0	(2)	(94)
Other expense	0	(16)	(602)	(18)
Interest and other income (expense), net	(29)	(72)	(701)	983
Net loss from continuing operations	(3,239)	(2,367)	(5,486)	(4,340)
Net loss from discontinued operations	(727)	(1,146)	(1,370)	(2,362)
Net loss	$ (3,966)	$ (3,513)	$ (6,856)	$ (6,702)
Net loss per common share from continuing operations, basic and diluted (in usd per share)	$ (0.06)	$ (0.15)	$ (0.14)	$ (0.29)
Net loss per common share from discontinued operations, basic and diluted (in usd per share)	(0.01)	(0.07)	(0.03)	(0.16)
Net loss per share common share, basic and diluted (in usd per share)	$ (0.07)	$ (0.23)	$ (0.17)	$ (0.44)
Weighted-average common shares outstanding used to calculate basic and diluted net loss per common share (in shares)	53,060,868	15,528,922	40,029,547	15,162,520