Schedule of Derivative Instruments in Statement of Financial Position at Fair Value (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative assets (liabilities), net	$ (57)	$ (130)
Not Designated as Hedging Instrument \| Foreign Exchange Contracts \| Prepayments
Derivatives, Fair Value [Line Items]
Derivative assets	389	1
Not Designated as Hedging Instrument \| Foreign Exchange Contracts \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ (446)	$ (131)

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 values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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No definition available.

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