Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Income Tax Contingency [Line Items]
Increase in effective tax rate due to GILTI provisions	8.00%
Valuation allowance with tax impact	$ 0.2
Gross unrecognized tax benefits	29.9	$ 29.6
Unrecognized tax benefits that would impact effective tax rate	$ 19.9
Maximum [Member]
Income Tax Contingency [Line Items]
Percentage of deduction in GILTI Income	50.00%
Gross unrecognized tax benefits balance may decrease within the next twelve months	$ 6.3
Minimum [Member]
Income Tax Contingency [Line Items]
Gross unrecognized tax benefits balance may decrease within the next twelve months	$ 0.0

Tax cuts and jobs act of 2017 change in effective tax rate due to global intangible low-taxed income provisions.

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Tax cuts and jobs act of 2017, deduction in global intangible low taxed income, percentage.

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Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unrecognized tax benefits.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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