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Derivative Instruments and Risk Management - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2019 | Mar. 31, 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 | $ 0.2 | $ (0.5)
Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member] | Accumulated Other Comprehensive Loss [Member] |  |
Derivative [Line Items] |  |
Amount of gain/(loss) recognized in income | $ 0.7 | $ 1.1

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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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