Other Assets (Detail) - Composition of Other Assets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Security deposits	$ 4,951us-gaap_DepositsAssetsNoncurrent	$ 5,505us-gaap_DepositsAssetsNoncurrent
Debt issuance costs	7,781	4,878
Benefit plan-related assets	43,293	42,367
Non-current deferred tax assets	17,960	24,371
Acquisition escrow - restricted cash	14,363	0
Other	4,001	4,510
Total other assets	$ 92,349us-gaap_OtherAssetsNoncurrent	$ 81,631us-gaap_OtherAssetsNoncurrent

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Net amount of long-term deferred finance costs capitalized at the end of the reporting period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

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-Subparagraph (SX 210.5-02.17)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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-Paragraph 4

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The amount for overfunded plans recognized in the balance sheet as a noncurrent asset associated with a defined benefit pension plan or other postretirement defined benefit plan.

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

-Publisher FASB

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-Topic 715

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Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment after one year or beyond the operating cycle, if longer.

+ References

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

+ References

No definition available.

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Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

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Cash and equivalents whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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