Components of Provision (Benefit) for Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Current tax provision, Federal									$ 407	$ 323	$ 570
Current tax provision, State									1,770	606	658
Current tax provision, Foreign									5,091	3,857	4,083
Current tax provision									7,268	4,786	5,311
Deferred tax provision, Federal									(39,237)	(18,369)	(2,928)
Deferred tax provision, State									(15,885)	(3,354)	898
Deferred tax provision, Foreign									(2,913)	(877)	(655)
Deferred tax provision									(58,035)	(22,600)	(2,685)
Income tax (benefit) provision	$ (49,694)	$ (238)	$ (1,007)	$ 172	$ (15,218)	$ (2,656)	$ (503)	$ 563	$ (50,767)	$ (17,814)	$ 2,626