Schedule of Derivative Instruments in Statement of Financial Position at Fair Value (Detail) - USD ($) $ in Thousands	Jul. 01, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Derivative assets (liabilities), net	$ (246)	$ (57)
Not Designated as Hedging Instrument \| Foreign currency forward contracts \| Prepayments
Derivatives, Fair Value [Line Items]
Derivative assets	7	389
Not Designated as Hedging Instrument \| Foreign currency forward contracts \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ (253)	$ (446)

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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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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