Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Net sales	$ 8,261	$ 18,335	$ 23,812	$ 47,154
Cost of sales	5,179	9,205	15,063	25,433
Gross profit	3,082	9,130	8,749	21,721
Operating expenses:
Product development	809	738	2,467	1,935
Selling, general, and administrative	5,423	4,651	15,323	11,620
Total operating expenses	6,232	5,389	17,790	13,555
(Loss) income from operations	(3,150)	3,741	(9,041)	8,166
Other expenses (income):
Interest expense	0	22	0	71
Other expenses (income)	16	(28)	7	9
(Loss) income from continuing operations before income taxes	(3,166)	3,747	(9,048)	8,086
Provision for (benefit from) income taxes	11	(651)	22	272
(Loss) income from continuing operations	(3,177)	4,398	(9,070)	7,814
Discontinued operations:
Loss from discontinued operations	0	(53)	0	(167)
Loss on disposal of discontinued operations	0	(89)	(12)	(161)
Loss from discontinued operations before income taxes	0	(142)	(12)	(328)
Benefit from income taxes	0	0	0	(10)
Loss from discontinued operations	0	(142)	(12)	(318)
Net (loss) income	$ (3,177)	$ 4,256	$ (9,082)	$ 7,496
Net (loss) income per share - basic:
From continuing operations (in dollars per share)	$ (0.27)	$ 0.42	$ (0.78)	$ 0.78
From discontinued operations (in dollars per share)	0.00	(0.01)	0.00	(0.03)
Net income (loss) per share - basic (in dollars per share)	(0.27)	0.41	(0.78)	0.75
Net (loss) income per share - diluted:
From continuing operations (in dollars per share)	(0.27)	0.41	(0.78)	0.75
From discontinued operations (in dollars per share)	0.00	(0.01)	0.00	(0.03)
Net income (loss) per share - diluted (in dollars per share)	$ (0.27)	$ 0.40	$ (0.78)	$ 0.72
Weighted average shares used in computing net (loss) income per share:
Basic (in shares)	11,690	10,310	11,666	10,002
Diluted (in shares)	11,690	10,665	11,666	10,342