Schedule of Derivative Instruments in Statement of Financial Position at Fair Value (Detail) - USD ($) $ in Thousands	Sep. 29, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Derivative assets (liabilities), net	$ (370)	$ (435)
Not Designated as Hedging Instrument \| Foreign currency forward contracts \| Prepayments
Derivatives, Fair Value [Line Items]
Derivative assets	119	79
Not Designated as Hedging Instrument \| Foreign currency forward contracts \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ (489)	$ (514)

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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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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