Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Income Statement [Abstract]
Total revenues	$ 10,865	$ 9,789	$ 31,350	$ 33,628
Cost of revenues	6,492	5,544	18,017	18,352
Gross profit	4,373	4,245	13,333	15,276
Operating expenses:
Research and development	1,428	1,256	4,452	4,007
Sales and marketing	3,769	2,378	10,346	7,212
General and administrative	2,422	1,858	6,380	5,546
Gain on sale of intellectual property	(175)		(175)
Total operating expenses	7,444	5,492	21,003	16,765
Loss from operations	(3,071)	(1,247)	(7,670)	(1,489)
Other expense, net	(16)	(51)	(19)	(83)
Loss from operations before provision for (benefit from) income taxes	(3,087)	(1,298)	(7,689)	(1,572)
Provision for (benefit from) income taxes	9	(627)	23	(674)
Net loss	$ (3,096)	$ (671)	$ (7,712)	$ (898)
Net loss per share:
Basic	$ (0.27)	$ (0.07)	$ (0.67)	$ (0.09)
Diluted	$ (0.27)	$ (0.07)	$ (0.67)	$ (0.09)
Weighted average shares used in computing net loss per common share:
Basic	11,569	10,129	11,544	10,083
Diluted	11,569	10,129	11,544	10,083