Fair Value Measurements - Financial Assets and (Liabilities) Required Fair Value Measurement on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Assets, Fair Value Disclosure [Abstract]
Assets	$ 40,599	$ 29,073
Liabilities, Fair Value Disclosure [Abstract]
Contingent consideration	124,848	21,943
Liabilities	142,023	51,324
Interest rate swaps [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	18,673	2,196
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	15,091	25,758
Energy derivative [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	11,880	26,872
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability		3,623
Foreign currency forward contracts [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	10,046	5
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	2,084
Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Assets	0	0
Liabilities, Fair Value Disclosure [Abstract]
Contingent consideration	0	0
Liabilities	0	0
Level 1 [Member] \| Interest rate swaps [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	0	0
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	0	0
Level 1 [Member] \| Energy derivative [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	0	0
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability		0
Level 1 [Member] \| Foreign currency forward contracts [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	0	0
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	0
Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Assets	28,719	2,201
Liabilities, Fair Value Disclosure [Abstract]
Contingent consideration	0	0
Liabilities	17,175	29,381
Level 2 [Member] \| Interest rate swaps [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	18,673	2,196
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	15,091	25,758
Level 2 [Member] \| Energy derivative [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	0	0
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability		3,623
Level 2 [Member] \| Foreign currency forward contracts [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	10,046	5
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	2,084
Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Assets	11,880	26,872
Liabilities, Fair Value Disclosure [Abstract]
Contingent consideration	124,848	21,943
Liabilities	124,848	21,943
Level 3 [Member] \| Interest rate swaps [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	0	0
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	0	0
Level 3 [Member] \| Energy derivative [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	11,880	26,872
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability		0
Level 3 [Member] \| Foreign currency forward contracts [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	0	$ 0
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	$ 0

No definition available.

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
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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.

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- Definition

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 liabilities not subject to a master netting arrangement and not elected to be offset.

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Aggregation of the liabilities reported on the balance sheet measured at fair value on a recurring basis by the entity.

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