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Derivatives - Additional Information (Detail) - Foreign Currency Forward Contracts - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Derivatives not Designated as Hedging Instruments |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |
Notional value of derivatives | $ 11,200 |  |
Contract expiring terms | 2018-08 |  |
(Loss) gain from foreign currency forward and option contracts not designated as hedging instruments | $ (829) | $ (306) | $ 2,552
Cash Flow Hedge |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |
Notional value of derivatives | $ 29,500 |  |
Contract maturity period | One year or less |  |
Contract expiring terms | 2018-09 |  |
Pre-tax loss to be reclassified into earnings within the next 12 months | $ (962) |  |

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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/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84234895&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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994 + Details
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- Definition The latest expiration date of foreign currency exchange contracts outstanding. + References No definition available. + Details
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- Definition Derivative maturity date range. + References No definition available. + Details
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