Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues:
Total revenues, net	$ 6,867	$ 4,280	$ 20,800	$ 15,609
Cost of revenues:
Impairment of Consumer Night Vision Business inventory			2,690
Total cost of revenues	4,488	4,002	16,335	12,264
Gross profit	2,379	278	4,465	3,345
Operating expenses:
Research and development	1,590	1,271	4,941	3,782
Selling, general and administrative	2,039	1,970	6,982	6,586
Total operating expenses	3,629	3,241	11,923	10,368
Loss from operations	(1,250)	(2,963)	(7,458)	(7,023)
Other income (expense):
Change in fair value of common stock warrant liability	1,311		387
Interest income (expense), net	1	(27)	(12)	(249)
Other income (expense), net	1	(2)		11
Total other income (expense)	1,313	(29)	375	(238)
Income (loss) before provision for income taxes	63	(2,992)	(7,083)	(7,261)
(Provision) benefit for income taxes
Net income (loss)	63	(2,992)	(7,083)	(7,261)
Less net income allocated to participating securities	9
Net income (loss) allocated to common shares	$ 54	$ (2,992)	$ (7,083)	$ (7,261)
Loss per share, basic	$ 0.00	$ (0.09)	$ (0.16)	$ (0.22)
Loss per share, diluted	$ 0.00	$ (0.09)	$ (0.16)	$ (0.22)
Weighted average number of shares outstanding:
Basic	45,149,717	34,972,589	44,182,379	33,214,262
Diluted	45,265,370	34,972,589	44,182,379	33,214,262
Product [Member]
Revenues:
Total revenues, net	$ 6,048	$ 4,014	$ 18,127	$ 13,050
Cost of revenues:
Cost of goods and services sold	3,926	3,802	12,256	10,918
Contract [Member]
Revenues:
Total revenues, net	819	266	2,673	2,559
Cost of revenues:
Cost of goods and services sold	$ 562	$ 200	$ 1,389	$ 1,346