Income Taxes - Schedule of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Federal	$ 36,045	$ 45,455	$ 38,357
State and local	3,848	7,087	7,180
Foreign	7,234	6,166	4,346
Total current provision	47,127	58,708	49,883
Deferred:
Federal	6,171	5,884	1,492
State and local	661	1,141	299
Foreign	(280)	(303)	189
Total deferred provision	6,552	6,722	1,980
Provision for income taxes	$ 53,679	$ 65,430	$ 51,863