Segments and Geographic Information - Schedule of Other Information by Segment (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues
Product revenues									$ 27,211	$ 22,891	$ 18,310
Service revenues									13,065	11,651	8,770
Royalties									14,297	3,745	6,313
Total revenues	$ 20,930	$ 11,556	$ 11,610	$ 10,477	$ 8,625	$ 10,993	$ 9,633	$ 9,036	54,573	38,287	33,393
Cost of product revenues									15,595	13,053	10,470
Cost of service revenues									8,698	8,361	7,219
Total cost of revenues									24,293	21,414	17,689
Gross profit	15,159	5,851	5,143	4,127	4,212	4,440	4,063	4,158	30,280	16,873	15,704
Total operating expenses	$ 6,042	$ 5,674	$ 7,420	$ 5,865	$ 5,335	$ 4,156	$ 4,976	$ 4,279	25,001	18,746	10,960
Total non-operating income									763	382	563
(Loss) income before income taxes									6,042	(1,491)	5,307
Product [Member]
Revenues
Product revenues									27,211	22,891	18,310
Royalties									14,297	3,745	6,313
Total revenues									41,508	26,636	24,623
Cost of product revenues									15,595	13,053	10,470
Total cost of revenues									15,595	13,053	10,470
Gross profit									25,913	13,583	14,153
Service [Member]
Revenues
Service revenues									13,065	11,651	8,770
Total revenues									13,065	11,651	8,770
Cost of service revenues									8,698	8,361	7,219
Total cost of revenues									8,698	8,361	7,219
Gross profit									$ 4,367	$ 3,290	$ 1,551