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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2019 | Dec. 31, 2018
Income Tax Contingency [Line Items] |  |
Increase in effective tax rate due to GILTI provisions | 8.00% |
Valuation allowance | $ 1.6 |
Gross unrecognized tax benefits | 30.6 | $ 29.6
Unrecognized tax benefits that would impact effective tax rate | $ 20.4 |
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 | $ 6.2 |
Minimum [Member] |  |
Income Tax Contingency [Line Items] |  |
Gross unrecognized tax benefits balance may decrease within the next twelve months | $ 0.0 |

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- Definition Tax cuts and jobs act of 2017 change in effective tax rate due to global intangible low-taxed income provisions. + References No definition available. + Details
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- Definition Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(3) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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