Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (Recurring [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financial assets
Deferred compensation plan	$ 6,805us-gaap_DeferredCompensationPlanAssets	$ 6,237us-gaap_DeferredCompensationPlanAssets
Derivatives	131us-gaap_DerivativeAssets	32us-gaap_DerivativeAssets
Total assets	6,936us-gaap_AssetsFairValueDisclosure	6,269us-gaap_AssetsFairValueDisclosure
Financial liabilities
Contingent consideration	(2,749)	(2,679)
Derivatives	(27)us-gaap_DerivativeLiabilities	(5)us-gaap_DerivativeLiabilities
Total liabilities	(2,776)us-gaap_LiabilitiesFairValueDisclosure	(2,684)us-gaap_LiabilitiesFairValueDisclosure
Level 1 [Member]
Financial assets
Deferred compensation plan	5,548	4,953
Total assets	5,548	4,953
Level 2 [Member]
Financial assets
Deferred compensation plan	1,257	1,284
Derivatives	131	32
Total assets	1,388	1,316
Financial liabilities
Derivatives	(27)	(5)
Total liabilities	(27)	(5)
Level 3 [Member]
Financial liabilities
Contingent consideration	(2,749)	(2,679)
Total liabilities	$ (2,749)	$ (2,679)

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

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of liability recognized arising from contingent consideration in a business combination.

+ References

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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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Fair value of financial and nonfinancial obligations.

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