Fair Value Measurements - Fair Value of Gross Position of Derivative Contracts in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Other current assets	$ 1,062	$ 3,698
Designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Gross amounts recognized	0	3,559
Gross amounts offset	1,029	(35)
Net amounts	1,029	3,524
Not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Gross amounts recognized	109	174
Gross amounts offset	(76)	0
Net amounts	$ 33	$ 174

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, before 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 elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before 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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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