Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Income Statement [Abstract]
Total revenues	$ 10,304	$ 10,002	$ 19,813	$ 20,485
Cost of revenues	6,036	5,507	11,623	11,525
Gross profit	4,268	4,495	8,190	8,960
Operating expenses:
Research and development	901	1,369	2,005	2,708
Sales and marketing	4,168	3,654	8,218	6,577
General and administrative	2,481	2,213	4,866	4,274
Total operating expenses	7,550	7,236	15,089	13,559
Loss from operations	(3,282)	(2,741)	(6,899)	(4,599)
Other income (expense), net	6	(1)	24	(3)
Loss from operations before provision for income taxes	(3,276)	(2,742)	(6,875)	(4,602)
Provision for income taxes	4	8	8	14
Net loss	$ (3,280)	$ (2,750)	$ (6,883)	$ (4,616)
Net loss per share:
Basic	$ (0.28)	$ (0.24)	$ (0.59)	$ (0.40)
Diluted	$ (0.28)	$ (0.24)	$ (0.59)	$ (0.40)
Weighted average shares used in computing net loss per common share:
Basic	11,644	11,546	11,636	11,532
Diluted	11,644	11,546	11,636	11,532