Income Taxes - Provision for (Benefit from) Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current Federal, State and Local, Tax Expense (Benefit) [Abstract]
U.S. Federal	$ (376)	$ 6,897	$ (7,593)
State	(9)	(2,926)	662
Foreign	13,858	14,751	11,721
Total current	13,473	18,722	4,790
Deferred:
U.S. Federal	(1,671)	15,304	(4,276)
State	(1,259)	732	(567)
Foreign	(8,451)	(7,283)	(6,248)
Total deferred	(11,381)	8,753	(11,091)
Provision for (benefit from) income taxes	$ 2,092	$ 27,475	$ (6,301)

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