Income Taxes - Schedule of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Current:
Federal	$ 11,331	$ 13,273	$ 28,676	$ 30,898
State and local	1,651	1,895	4,579	5,055
Foreign	1,191	1,714	4,234	4,599
Total current provision	14,173	16,882	37,489	40,552
Deferred:
Federal	(930)	(918)	130	6,895
State and local	(158)	(154)	(64)	964
Foreign	2	(374)	226	(143)
Total deferred provision	(1,086)	(1,446)	292	7,716
Provision for income taxes	$ 13,087	$ 15,436	$ 37,781	$ 48,268