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Derivative Instruments and Risk Management - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Derivative [Line Items] |  |
Interest rate swaps notional value | $ 132,500,000 |
Foreign currency forward exchange contracts notional value | $ 108,700,000 |
Maximum [Member] |  |
Derivative [Line Items] |  |
Maturity period of foreign currency forward exchange contracts | 1 year |
Interest Rate Swaps [Member] | Maximum [Member] |  |
Derivative [Line Items] |  |
Derivative fixed interest rate | 1.67% |
Interest Rate Swaps [Member] | Minimum [Member] |  |
Derivative [Line Items] |  |
Derivative fixed interest rate | 1.42% |
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 | $ (1,800,000) | $ (900,000)
Designated as Hedging Instrument [Member] | Interest Rate Swaps [Member] | Accumulated Other Comprehensive Loss [Member] |  |
Derivative [Line Items] |  |
Amount of gain/(loss) recognized in income | $ 400,000 | $ 1,100,000

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- Definition Notional value of interest rate swap agreement. + References No definition available. + Details
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- Definition Fixed interest rate related to the interest rate derivative. + References No definition available. + Details
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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 Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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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