Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Components Of Income Tax Expense Benefit [Line Items]
Corporate income tax rate			35.00%	35.00%	35.00%
Additional income tax expense benefit	$ 8,300
Tax cuts and jobs act of 2017 change in tax rate deferred tax assets and liability expected to reserve in future			$ 8,600
Change of intention for foreign earnings			0	$ 1,300
Tax cuts and jobs act of 2017 change in provisional income tax benefit			300
Change in estimate, increase in net income				$ 2,400
Change in estimate, increase in earnings per share				$ 0.13
Net increase in valuation allowance			4,600
Unremitted foreign earnings	335,700		$ 335,700	$ 372,500
Minimum percentage of income tax benefit			50.00%
Gross unrecognized tax benefit	22,500		$ 22,500	18,400
Interest and penalties on unrecognized tax benefits			2,300	2,100	$ 200
Accrued interest and penalties related to unrecognized tax benefits	5,300		5,300	$ 3,000
Minimum [Member]
Components Of Income Tax Expense Benefit [Line Items]
Decrease in unrecognized tax benefits	2,400		2,400
Maximum [Member]
Components Of Income Tax Expense Benefit [Line Items]
Decrease in unrecognized tax benefits	3,600		3,600
State [Member]
Components Of Income Tax Expense Benefit [Line Items]
Operating loss carry forwards, net of tax	11,600		11,600
Foreign Jurisdictions [Member]
Components Of Income Tax Expense Benefit [Line Items]
Operating loss carry forwards, net of tax	$ 167,300		$ 167,300
Scenario, Forecast [Member]
Components Of Income Tax Expense Benefit [Line Items]
Corporate income tax rate		21.00%