Information about Geographic Areas and Operating Segments - Revenue and Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Total revenue:
Total revenue	$ 22,467	$ 26,435	$ 70,644	$ 81,573
Long-lived assets:
Total long-lived assets	5,511		5,511		$ 5,945
North America [Member]
Total revenue:
Total revenue	20,917	23,654	66,275	74,415
Long-lived assets:
Total long-lived assets	981		981		1,353
Asia [Member]
Total revenue:
Total revenue	1,018	1,055	1,847	3,043
Long-lived assets:
Total long-lived assets	264		264		247
Europe [Member]
Total revenue:
Total revenue	532	$ 1,726	2,522	$ 4,115
Long-lived assets:
Total long-lived assets	$ 4,266		$ 4,266		$ 4,345