Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues
Product revenues	$ 32,688	$ 27,211	$ 22,891
Service revenues	17,291	13,065	11,651
Royalties		14,297	3,745
Total revenues	49,979	54,573	38,287
Cost of product revenues	19,013	15,595	13,053
Cost of service revenues	9,948	8,698	8,361
Total cost of revenues	28,961	24,293	21,414
Gross profit	21,018	30,280	16,873
Operating expenses
Sales and marketing	1,859	1,259	1,249
Research and development	6,860	9,676	7,039
General and administrative	15,385	14,066	10,458
Restructuring charge	777
Total operating expenses	24,881	25,001	18,746
(Loss) income from operations	(3,863)	5,279	(1,873)
Interest expense, net	(130)	(97)	(106)
Other income, net	1,747	860	488
(Loss) income before income taxes	(2,246)	6,042	(1,491)
Income tax (benefit) expense	(186)	91	5
Net (loss) income	(2,060)	5,951	(1,496)
Adjustments attributable to preferred stockholders	(445)	28	28
Net (loss) income available to common stockholders	$ (1,615)	$ 5,923	$ (1,524)
Basic net (loss) income per common share	$ (0.15)	$ 0.55	$ (0.14)
Diluted net (loss) income per common share	$ (0.15)	$ 0.55	$ (0.14)
Basic weighted average common shares outstanding	10,824	10,795	10,774
Diluted weighted average common shares outstanding	10,824	10,891	10,774