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Derivatives - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Foreign Currency Forward Contracts | Cash Flow Hedge
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional value of derivatives	$ 1,000,000
Contract maturity period	one year or less
Contract expiring terms	2021-01
Maximum length of time hedged in cash flow hedge	12 months
Pre-tax gain to be reclassified into earnings within the next 12 months	$ 402,000
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	$ 4,600,000
Contract expiring terms	2021-01
(Loss) gain from foreign currency forward and option contracts not designated as hedging instruments	$ (490,000)	$ (540,000)	$ 129,000

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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.

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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
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Nominal or face amount used to calculate payment on derivative.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Topic 815
-SubTopic 10
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-Publisher FASB
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-Section 50
-Paragraph 1A
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-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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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
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-Section 50
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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.

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Derivative maturity date range.

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