Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Revenues	$ 18,683	$ 20,190	$ 33,786	$ 38,851
Costs and expenses:
Cost of sales	11,547	11,677	19,984	22,487
Selling, general and administrative	8,400	8,959	16,603	17,703
Research and development	982	225	1,854	469
Costs and expenses:	20,929	20,861	38,441	40,659
Operating loss	(2,246)	(671)	(4,655)	(1,808)
Interest expense	(3)	(34)	(30)	(63)
Interest income	7	6	14	17
Other expense	(65)	(39)	(161)	(69)
Loss before income taxes	(2,307)	(738)	(4,832)	(1,923)
Income tax benefit	936	18	1,807	117
Net loss	$ (1,371)	$ (720)	$ (3,025)	$ (1,806)
Net loss per common share:
Basic (in dollars per share)	$ (0.06)	$ (0.03)	$ (0.13)	$ (0.08)
Diluted (in dollars per share)	$ (0.06)	$ (0.03)	$ (0.13)	$ (0.08)
Weighted-average number of common shares outstanding:
Basic (in shares)	23,140	22,814	23,034	22,728
Diluted (in shares)	23,140	22,814	23,034	22,728