Fair Value of Financial Instruments - Additional Information (Detail) - Cash Flow Hedging [Member] $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)
Foreign exchange contracts [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notional amount of cash flow hedge	$ 165,559
Maturity date of foreign currency derivative contracts	Dec. 14, 2018
Interest Rate Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notional amount of cash flow hedge	$ 150,000
Derivative, Maturity Date	Sep. 30, 2018
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	$ 515

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

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- Definition

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve 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

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- Definition

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

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