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Derivatives - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Foreign Currency Forward Contracts | Cash Flow Hedge |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |
Notional value of derivatives | $ 43,900,000 |  | $ 43,900,000 |
Contract maturity period |  |  | one year or less |
Contract expiring terms |  |  | 2020-03 |
Maximum length of time hedged in cash flow hedge |  |  | 12 months |
Pre-tax gain to be reclassified into earnings within the next 12 months | 545,000 |  | $ 545,000 |
Foreign Exchange Forward And Option Contracts [Member] | Not Designated as Hedging Instrument, Economic Hedge [Member] |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |
Notional value of derivatives | 15,160,000 |  | $ 15,160,000 |
Contract expiring terms |  |  | 2019-08 |
(Loss) gain from foreign currency forward and option contracts not designated as hedging instruments | $ (190,000) | $ 180,000 | $ 303,000 | $ 191,000

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + 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 Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CC -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109998890-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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- Definition The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994 + Details
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- Definition Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994 + Details
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