Income Taxes - Schedule of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Current:
Federal	$ 11,041	$ 9,280	$ 28,131	$ 22,297
State and local	2,036	1,583	5,234	4,356
Foreign	1,234	227	3,189	520
Total current provision	14,311	11,090	36,554	27,173
Deferred:
Federal	(1,246)	(354)	2,658	3,979
State and local	(209)	(73)	420	512
Foreign	(218)	101	(264)	213
Total deferred provision	(1,673)	(326)	2,814	4,704
Provision for income taxes	$ 12,638	$ 10,764	$ 39,368	$ 31,877