Income Taxes - Additional Information (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 [Line Items]
Tax benefit related to 2017 Tax Act									$ (44,900)
Reduction to income tax expense 2017 Tax Act									65,100
Provisional transition tax expense									18,700
Transition tax payment next twelve months	$ 2,500								2,500
Valuation allowance	21,621				$ 18,900				21,621	$ 18,900
Deferred tax liability not recognized related to tax basis difference in investment in foreign subsidiaries	13,400								13,400
Income tax provision (benefit)	(38,458)	$ 9,197	$ 527	$ 7,877	(1,832)	$ 10,292	$ 15,437	$ 18,386	(20,857)	42,283	$ 39,333
Liability for uncertain tax positions	$ 2,700				$ 2,700				$ 2,700	$ 2,700
Minimum
Income Tax [Line Items]
Operating loss carryforward period									20 years
Maximum
Income Tax [Line Items]
Operating loss carryforward period									indefinite