Derivative Instruments and Hedging Strategies - Additional Information (Detail) - Foreign Currency Derivatives $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($)
Derivative [Line Items]
Amount reclassified from accumulated other comprehensive loss to earnings as related to forecasted revenue and operating expense transactions	$ 2.2
Maximum length of time over which hedging its exposure to the reduction in value of forecasted foreign currency cash flows through foreign currency forward contracts	12 months
Maximum
Derivative [Line Items]
Maturity period of foreign currency derivatives	Jun. 30, 2021

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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

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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.

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- Definition

Date the foreign currency exchange rate derivatives mature or expire, in CCYY-MM-DD format.

+ References

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- Definition

Maximum amount of time remaining before foreign currency exchange rate derivatives mature or expire, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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