Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Financial Assets
Derivatives	$ 32
Financial Liabilities
Derivatives	(44)	(353)
Recurring [Member]
Financial Assets
Escrow account		898
Deferred compensation plan assets	5,627	5,280
Derivatives	32
Total Assets	5,659	6,178
Financial Liabilities
Derivatives	(44)	(353)
Level 1 [Member] \| Recurring [Member]
Financial Assets
Escrow account		898
Deferred compensation plan assets	5,627	5,280
Derivatives
Total Assets	5,627	6,178
Financial Liabilities
Derivatives
Level 2 [Member] \| Recurring [Member]
Financial Assets
Escrow account
Deferred compensation plan assets
Derivatives	32
Total Assets	32
Financial Liabilities
Derivatives	(44)	(353)
Level 3 [Member] \| Recurring [Member]
Financial Assets
Escrow account
Deferred compensation plan assets
Derivatives
Total Assets
Financial Liabilities
Derivatives

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)

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

+ 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 210.5-02.17)

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

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-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

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-Paragraph 3

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

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-Paragraph 6

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226008-175313

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Fair value, after the effects of master netting arrangements, of a financial liability or 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.

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- Definition

Other long-term assets not otherwise listed in the existing taxonomy that are pledged or subject to withdrawal restrictions.

+ References

No definition available.

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