Segment and Geographical Information - Schedule of Revenues Attributed to Geographic Location (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting, Revenue Reconciling Item [Line Items]
Total consolidated revenues	$ 47,003	$ 42,996	$ 46,633	$ 48,647	$ 53,627	$ 51,013	$ 53,167	$ 49,173	$ 185,279	$ 206,980	$ 204,724
United States [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Total consolidated revenues									114,578	137,060	134,951
International [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Total consolidated revenues									$ 70,701	$ 69,920	$ 69,773