Information about Geographic Areas - Revenue and Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Total revenue:
Total revenue	$ 22,738	$ 28,873	$ 48,177	$ 55,138
Long-lived assets:
Total long-lived assets	5,621		5,621		$ 5,945
North America [Member]
Total revenue:
Total revenue	21,291	27,015	45,359	50,761
Long-lived assets:
Total long-lived assets	1,062		1,062		1,353
Asia [Member]
Total revenue:
Total revenue	554	603	828	1,988
Long-lived assets:
Total long-lived assets	265		265		247
Europe [Member]
Total revenue:
Total revenue	893	$ 1,255	1,990	$ 2,389
Long-lived assets:
Total long-lived assets	$ 4,294		$ 4,294		$ 4,345