Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Revenue	$ 7,175	$ 6,470	$ 12,196	$ 13,523
Cost of revenue	3,402	3,008	5,988	6,293
Gross profit	3,773	3,462	6,208	7,230
Operating expenses
Research and development	1,600	1,578	3,076	3,789
Selling, general and administrative	1,828	1,572	3,497	3,193
Total operating expenses	3,428	3,150	6,573	6,982
Income (loss) from operations	345	312	(365)	248
Other income (expense)	52	(165)	39	224
Income (loss) before income taxes	397	147	(326)	472
Income tax provision (benefits)	62	(54)	(43)	(202)
Net income (loss)	$ 335	$ 201	$ (283)	$ 674
Net income (loss) per share:
Basic	$ 0.02	$ 0.01	$ (0.02)	$ 0.04
Diluted	$ 0.02	$ 0.01	$ (0.02)	$ 0.04
Weighted average shares outstanding in computing net income (loss) per share
Basic	17,228,184	16,940,745	17,200,595	16,883,574
Diluted	17,814,303	18,017,564	17,200,595	18,050,768