Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 30, 2017
Income Statement [Abstract]
Sales, net	$ 31,557	$ 21,201
Cost of sales	15,502	10,724
Gross profit	16,055	10,477
Operating expenses:
Sales and marketing	16,537	4,459
Research and development	5,478	4,007
General and administrative	27,137	17,642
Other	75	746
Operating expenses	49,227	26,854
Operating loss	(33,172)	(16,377)
Nonoperating expense:
Interest expense, net	(79)	(153)
Other	(65)	0
Nonoperating expenses	(144)	(153)
Loss from continuing operations	(33,316)	(16,530)
Loss from discontinued operations	0	(315)
Gain on sale of discontinued operations	0	5,467
Income from discontinued operations, net	0	5,152
Net loss	$ (33,316)	$ (11,378)
Basic and diluted earnings (loss) per common share:
Loss from continuing operations	$ (0.61)	$ (0.37)
Earnings from discontinued operations	0.00	0.11
Basic and diluted loss per common share	$ (0.61)	$ (0.26)
Basic and diluted weighted average common shares outstanding	55,006	44,599