Summary of Non-Designated Forward Foreign Currency Exchange Contracts Outstanding (Detail) - Foreign exchange contracts	12 Months Ended
Dec. 31, 2016 EUR (€) Derivative	Dec. 31, 2016 GBP (£) Derivative
Maximum
Derivative [Line Items]
Maturity	Dec. 31, 2019
Not Designated as Hedging Instrument
Derivative [Line Items]
Number of Contracts	2	2
Not Designated as Hedging Instrument \| Euros \| Purchase
Derivative [Line Items]
Number of Contracts	1	1
Aggregate Notional Amount in Foreign Currency \| €	€ 94,900,000
Maturity	Jan. 01, 2017
Not Designated as Hedging Instrument \| British Pounds \| Sell
Derivative [Line Items]
Number of Contracts	1	1
Aggregate Notional Amount in Foreign Currency \| £		£ 2,700,000
Maturity	Jan. 01, 2017

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

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

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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

Number of foreign currency exchange rate derivatives held by the entity at the reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

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