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Derivative Instruments and Risk Management - Additional Information (Detail) - USD ($) $ in Millions | 9 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018
Not Designated as Hedging Instrument [Member] | Foreign Currency Forward Exchange Contracts [Member] | Other net income/(expense) [Member] |  |
Derivative [Line Items] |  |
Amount of gain/(loss) recognized in income | $ 2.9 | $ (1.6)
Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member] | Accumulated Other Comprehensive Loss [Member] |  |
Derivative [Line Items] |  |
Amount of gain/(loss) recognized in income | $ (1.8) | $ 1.2

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- Definition 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. + References No definition available. + Details
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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959 + Details
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