Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Debt instrument London interbank offered rate.

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- Definition

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Financial Instruments [Line Items]

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-SubTopic 10
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Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 28, 2018	Sep. 29, 2017	Sep. 28, 2018	Sep. 29, 2017	Sep. 30, 2015
Financial Instruments [Line Items]
Effect of derivative instruments not designated as hedging instruments on income	$ (100,000)	$ 0	$ (100,000)	$ 0
Derivatives in Cash Flow Hedging Relationship [Member]
Financial Instruments [Line Items]
Gains (losses) recognized in income on derivatives that are excluded from effectiveness testing and ineffective portion	0	$ 0	$ 0	$ 0
FDS [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Financial Instruments [Line Items]
Non-Designated Derivatives, description			A portion of FDS’s forward contracts with a total notional amount of $3.6 million is not designated as a hedging instrument. The Company recognizes gains and losses on these contracts, as well any related costs, in interest and other income (expense), net.
Forward Contracts [Member] \| FDS [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Financial Instruments [Line Items]
Derivative instrument, notional amount	$ 3,600,000		$ 3,600,000
East West Bank and City National Bank [Member] \| Interest Rate Swap [Member]
Financial Instruments [Line Items]
Derivative instrument, notional amount					$ 20,000,000
Credit Agreement [Member] \| Interest Rate Swap [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Debt instrument LIBOR rate					0.99%