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Financial Instruments - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Derivative [Line Items] |  |
Maximum length of time to hedges exposure to foreign currency exchange risk | 12 months |
Foreign Currency Derivatives |  |
Derivative [Line Items] |  |
Notional Value | $ 13,299,000 | $ 14,449,000
Interest Rate Swap |  |
Derivative [Line Items] |  |
Hedge Ineffectiveness Incurred | $ 0 | $ 0

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- Definition Maximum period of time the entity is hedging its exposure to variability in future cash flows for forecasted transactions, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes forecasted transactions related to payment of variable interest on existing financial instruments. + 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=121549185&loc=d3e80748-113994 + Details
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