Fair Value Measurements - Financial Assets and (Liabilities) Required Fair Value Measurement on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Assets, Fair Value Disclosure [Abstract]
Derivative asset		$ 29,073
Assets	$ 33,489
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability		51,324
Contingent Consideration	128,000	21,943
Liabilities	155,652
Interest rate swaps [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	11,475	2,196
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	25,038	25,758
Energy derivative [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	12,198	26,872
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability		3,623
Foreign currency forward contracts [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	9,816	5
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	2,614
Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset		0
Assets	0
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability		0
Contingent Consideration	0	0
Liabilities	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]
Derivative asset		2,201
Assets	21,291
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability		29,381
Contingent Consideration	0	0
Liabilities	27,652
Level 2 [Member] \| Interest rate swaps [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset	11,475	2,196
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	25,038	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	9,816	5
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability	2,614
Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative asset		26,872
Assets	12,198
Liabilities, Fair Value Disclosure [Abstract]
Derivative liability		21,943
Contingent Consideration	128,000	21,943
Liabilities	128,000
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	12,198	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

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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.

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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.

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

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