Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Income Statement [Abstract]
Total revenues	$ 10,243	$ 10,865	$ 10,002	$ 10,483	$ 12,530	$ 9,789	$ 11,908	$ 11,931	$ 41,593	$ 46,158	$ 41,757
Cost of revenues	8,073	6,492	5,507	6,018	6,967	5,544	6,174	6,634	26,090	25,319	21,804
Gross profit	2,170	4,373	4,495	4,465	5,563	4,245	5,734	5,297	15,503	20,839	19,953
Operating expenses:
Research and development	1,278	1,428	1,528	1,496	1,358	1,256	1,392	1,359	5,730	5,365	5,214
Sales and marketing	4,195	3,769	3,654	2,923	3,069	2,378	2,405	2,429	14,541	10,281	8,901
General and administrative	1,880	2,422	2,054	1,904	2,092	1,858	2,331	1,357	8,260	7,638	5,550
Gain on sale of intellectual property		(175)							(175)
Impairment of long-lived assets	35				120				35	120
Total operating expenses	7,388	7,444	7,236	6,323	6,639	5,492	6,128	5,145	28,391	23,404	19,665
(Loss) income from operations	(5,218)	(3,071)	(2,741)	(1,858)	(1,076)	(1,247)	(394)	152	(12,888)	(2,565)	288
Other (expense) income, net	(88)	(16)	(1)	(2)	(8)	(51)	(21)	(11)	(107)	(91)	3
(Loss) income from operations before (benefit from) provision for income taxes	(5,306)	(3,087)	(2,742)	(1,860)	(1,084)	(1,298)	(415)	141	(12,995)	(2,656)	291
(Benefit from) provision for income taxes	(151)	9	8	6	9,731	(627)	(87)	40	(128)	9,057	(183)
Net (loss) income	$ (5,155)	$ (3,096)	$ (2,750)	$ (1,866)	$ (10,815)	$ (671)	$ (328)	$ 101	$ (12,867)	$ (11,713)	$ 474
Net (loss) income per share:
Basic	$ (0.44)	$ (0.27)	$ (0.24)	$ (0.16)	$ (1.04)	$ (0.07)	$ (0.03)	$ 0.01	$ (1.11)	$ (1.15)	$ 0.05
Diluted	$ (0.44)	$ (0.27)	$ (0.24)	$ (0.16)	$ (1.04)	$ (0.07)	$ (0.03)	$ 0.01	$ (1.11)	$ (1.15)	$ 0.05
Weighted average shares used in computing net (loss) income per common share:
Basic									11,555	10,173	9,962
Diluted									11,555	10,173	10,128