Fair Value Measurements - Financial Assets and Liabilities Measured on a Recurring Basis at Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financial assets and liabilities measured on a recurring basis at fair value
Mutual fund assets	$ 20,217us-gaap_LongTermInvestments	$ 18,305us-gaap_LongTermInvestments
Derivative assets:
Foreign currency contracts	73	74
Total assets at fair value	20,290us-gaap_AssetsFairValueDisclosure	18,379us-gaap_AssetsFairValueDisclosure
Derivative liabilities:
Foreign currency contracts	628	165
Interest rate contracts		20
Total liabilities at fair value		185us-gaap_LiabilitiesFairValueDisclosure
Level 1 [Member]
Financial assets and liabilities measured on a recurring basis at fair value
Mutual fund assets	20,217	18,305
Derivative assets:
Total assets at fair value	20,217	18,305
Level 2 [Member]
Derivative assets:
Foreign currency contracts	73	74
Total assets at fair value	73	74
Derivative liabilities:
Foreign currency contracts	628	165
Interest rate contracts		20
Total liabilities at fair value		$ 185

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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