Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Net sales	$ 3,177	$ 4,659
Cost of sales	3,079	3,843
Gross profit	98	816
Operating expenses:
Product development	526	629
Selling, general, and administrative	2,241	2,647
Restructuring	134	(50)
Total operating expenses	2,901	3,226
Loss from operations	(2,803)	(2,410)
Other expenses (income):
Interest expense	43	1
Other expenses (income)	19	(21)
Loss from operations before income taxes	(2,865)	(2,390)
Provision for income taxes	0	0
Net loss	$ (2,865)	$ (2,390)
Net loss per share - basic and diluted (in dollars per share)	$ (0.24)	$ (0.20)
Weighted average shares used in computing net loss per share:
Basic and diluted (in shares)	12,126	11,900