Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Revenues	$ 2,025	$ 3,476	$ 6,654	$ 10,881
Cost of revenues	1,117	2,809	3,943	8,462
Gross profit	908	667	2,711	2,419
Operating expenses:
Research and development	520	1,085	1,840	2,996
Selling, general and administrative	1,233	1,855	3,967	6,462
Severance and other charges	0	235	0	(384)
Total operating expenses	1,753	3,175	5,807	9,074
Loss from continuing operations	(845)	(2,508)	(3,096)	(6,655)
Other income (expense):
Interest expense, net	0	(95)	0	(235)
Loss on extinguishment of debt	0	0	0	(194)
Gain on sale of DuraFit business	0	805	0	805
Gain (loss) on change in fair value of liability-classified warrants	57	738	591	404
Other expense, net	43	(149)	95	(67)
Total other income (expense)	100	1,299	686	713
Loss from continuing operations before income taxes	(745)	(1,209)	(2,410)	(5,942)
Income tax expense from continuing operations	17	(119)	758	49
Net loss from continuing operations	(762)	(1,090)	(3,168)	(5,991)
Net (loss) income from discontinued operations	(645)	730	(486)	2,149
Net loss	(1,407)	(360)	(3,654)	(3,842)
Foreign currency translation adjustments	(52)	129	(170)	350
Comprehensive loss	$ (1,459)	$ (231)	$ (3,824)	$ (3,492)
Basic and diluted net (loss) income per common share:
Net loss from continuing operations (in dollars per share)	$ (0.20)	$ (0.35)	$ (0.93)	$ (1.90)
Net (loss) income from discontinued operations - Basic (in usd per share)	(0.17)	0.24	(0.14)	0.68
Net (loss) income from discontinued operations - Diluted (in usd per share)	(0.17)	0.24	(0.14)	0.68
Net loss (in dollars per share)	$ (0.37)	$ (0.11)	$ (1.08)	$ (1.22)
Weighted average shares outstanding - basic and diluted (in shares)	3,839	3,152	3,394	3,145
Weighted average number of shares outstanding, diluted (in shares)	3,839	3,152	3,394	3,175