Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Loss Carryforwards [Line Items]
Reduction to net deferred tax asset	$ 20,413
U.S. tax act - transition tax	35,378
Foreign tax credit carryforwards	1,707
Tax provision liability due in 2018	2,694
Tax provision liability due in 2019	2,694
Tax provision liability due in 2020	2,694
Tax provision liability due in 2021	2,694
Tax provision liability due in 2022	2,694
Tax provision liability due 2023 - 2025	20,201
Unremitted foreign earnings	495,000
Payments for income taxes net of refunds	67,782	$ 131,001	$ 76,206
Tax loss carryforward domestic	6,731
Tax loss carry forward foreign	64,972
State tax credits carry forward	240
Recognition of unrecognized tax benefit upon which the effective rate would change	2,283
Unrecognized tax benefits, exclusive of interest	2,283	3,197	5,843	$ 8,314
Accrued tax provision of interest expense	(17)	(347)	63
Unrecognized tax benefits interest on income taxes accrued	124
Her Majesty's Revenue and Customs (HMRC)
Operating Loss Carryforwards [Line Items]
Valuation allowance	18,915	0	0
State Administration of Taxation, China
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ (6,671)	$ (2,441)	$ (18,200)