Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Net sales	$ 6,011	$ 7,126	$ 10,117	$ 15,551
Cost of sales	4,510	4,604	8,055	9,884
Gross profit	1,501	2,522	2,062	5,667
Operating expenses:
Product development	763	854	1,534	1,658
Selling, general, and administrative	2,778	5,590	6,409	9,900
Restructuring	1,060	0	1,734	0
Total operating expenses	4,601	6,444	9,677	11,558
Loss from operations	(3,100)	(3,922)	(7,615)	(5,891)
Other expenses (income):
Other expenses (income)	14	(6)	21	(9)
Loss from continuing operations before income taxes	(3,114)	(3,916)	(7,636)	(5,882)
Provision for income taxes	0	0	0	11
Loss from continuing operations	(3,114)	(3,916)	(7,636)	(5,893)
Discontinued operations:
Loss on disposal of discontinued operations	0	0	0	(12)
Loss from discontinued operations	0	0	0	(12)
Net loss	$ (3,114)	$ (3,916)	$ (7,636)	$ (5,905)
Net loss per share - basic:
From continuing operations (in dollars per share)	$ (0.26)	$ (0.34)	$ (0.65)	$ (0.51)
From discontinued operations (in dollars per share)	0.00	0.00	0.00	0.00
Net loss per share - basic (in dollars per share)	(0.26)	(0.34)	(0.65)	(0.51)
Net loss per share - diluted:
From continuing operations (in dollars per share)	(0.26)	(0.34)	(0.65)	(0.51)
From discontinued operations (in dollars per share)	0.00	0.00	0.00	0.00
Net loss per share - diluted (in dollars per share)	$ (0.26)	$ (0.34)	$ (0.65)	$ (0.51)
Weighted average shares used in computing net loss per share:
Basic (in shares)	11,791	11,657	11,755	11,653
Diluted (in shares)	11,791	11,657	11,755	11,653