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)
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-Article 12
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Debt instrument London interbank offered rate.

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Derivative of instruments not designated as hedging instruments description of terms.

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Financial Instruments [Line Items]

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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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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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. 24, 2016	Jun. 26, 2015	Jun. 24, 2016	Jun. 26, 2015	Mar. 25, 2016	Dec. 25, 2015	Sep. 30, 2015	Mar. 27, 2015
Financial Instruments [Line Items]
Cash and cash equivalents	$ 44,053,000	$ 76,614,000	$ 44,053,000	$ 76,614,000	$ 50,103,000	$ 50,103,000		$ 78,997,000
Effective portion of cash flow hedge before tax effect			100,000
Cash flow hedge, expected to be reclassified from AOCI into earnings			$ 100,000
Miconex [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Financial Instruments [Line Items]
Non-Designated Derivatives, description			The Miconex interest swap to convert the variable interest rates on Miconex debt to fixed rates with a total notional amount of $0.4 million is not designated as a hedging instrument. The Company recognizes gains and losses on this contract, as well any related costs in interest and other income (expense), net.
Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Outstanding amounts	32,100,000		$ 32,100,000
Interest Rate Swap [Member] \| Miconex [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Financial Instruments [Line Items]
Derivative instrument, notional amount	400,000		$ 400,000
East West 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]
Derivative instrument, notional amount							$ 20,000,000
Debt instrument variable interest rate			2.75%
Credit Agreement [Member] \| Interest Rate Swap [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Derivative instrument, notional amount	$ 17,100,000		$ 17,100,000
Debt instrument LIBOR rate							0.99%
Debt instrument interest rate	3.74%		3.74%
Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Debt instrument variable interest rate			0.45%
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] \| East West and City National Bank [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Debt instrument interest rate	3.74%		3.74%
Outstanding amounts	$ 32,100,000		$ 32,100,000
Derivatives in Cash Flow Hedging Relationship [Member] \| East West and City National Bank [Member] \| Interest Rate Swap [Member] \| Term Loan Credit Facility [Member]
Financial Instruments [Line Items]
Derivative instrument, notional amount	17,100,000		17,100,000
Money Market Fund Deposits [Member]
Financial Instruments [Line Items]
Cash and cash equivalents	0		0			600,000
Money Market Fund Deposits [Member] \| Level 1 [Member]
Financial Instruments [Line Items]
Fair value of cash and cash equivalents	$ 0		$ 0			$ 600,000