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

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Debt instrument London interbank offered rate.

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Financial Instruments [Line Items]

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Sep. 30, 2015
Financial Instruments [Line Items]
Effect of derivative instruments not designated as hedging instruments on income	$ (600,000)	$ 0	$ (600,000)	$ 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 $4.7 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	4,700,000		$ 4,700,000
Maximum [Member]
Financial Instruments [Line Items]
Effective portion of cash flow hedge before tax effect			100,000
Cash flow hedge, expected to be reclassified from AOCI into earnings			100,000
Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Outstanding amounts	$ 7,400,000		$ 7,400,000
Interest Rate Swap [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Derivative instrument, notional amount					$ 20,000,000
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] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Debt instrument interest rate	2.00%		2.00%
Outstanding amounts	$ 7,400,000		$ 7,400,000
Credit Agreement [Member] \| Interest Rate Swap [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Derivative instrument, notional amount	$ 4,700,000		$ 4,700,000
Debt instrument LIBOR rate					0.99%
Debt instrument interest rate	2.99%		2.99%
Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Debt instrument variable interest rate			1.98%
Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Interest Rate Swap [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Debt instrument variable interest rate			1.98%
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
Derivatives in Cash Flow Hedging Relationship [Member] \| Forward Contracts [Member]
Financial Instruments [Line Items]
Effective portion of cash flow hedge before tax effect	(82,000)	841,000	(71,000)	841,000
Derivatives in Cash Flow Hedging Relationship [Member] \| Interest Rate Swap [Member]
Financial Instruments [Line Items]
Effective portion of cash flow hedge before tax effect	$ (21,000)	$ (2,000)	$ (36,000)	$ 11,000
Derivatives in Cash Flow Hedging Relationship [Member] \| East West Bank and City National Bank [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Debt instrument interest rate	2.99%		2.99%
Outstanding amounts	$ 7,400,000		$ 7,400,000
Derivatives in Cash Flow Hedging Relationship [Member] \| East West Bank and City National Bank [Member] \| Interest Rate Swap [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Derivative instrument, notional amount	$ 4,700,000		$ 4,700,000