Revolving Line of Credit - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Commitment fee	0.15%
Credit facility, borrowing outstanding	$ 0	$ 0
EBITDA to interest expense ratio	1263900.00%
EBITDA to interest expense, minimum allowable ratio	200.00%
Total funded debt to EBITDA ratio	0.00%
Total funded debt to EBITDA, maximum allowable ratio	250.00%
Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit, current borrowing capacity	$ 150,000,000
Basis spread on variable rate	0.45%
Line of credit, expiration date	Mar. 31, 2019
Debt, covenant compliance	The Company was in compliance with all financial covenants as of December 30, 2017 and December 31, 2016.
Revolving Credit Facility \| Alternative Prime Rate
Debt Instrument [Line Items]
Debt interest rate at end of period	4.50%
Revolving Credit Facility \| LIBOR rate
Debt Instrument [Line Items]
Debt interest rate at end of period	1.49%

Debt Instrument Interest Coverage Ratio

No definition available.

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- Definition

Debt To Earnings Before Interest Tax Depreciation And Amortization Ratio

+ References

No definition available.

+ Details

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- Definition

Debt to Earnings Before Interest Taxes Depreciation Amortization Ratio Maximum for Covenant Compliance

+ References

No definition available.

+ Details

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- Definition

Interest Coverage Ratio Minimum for Covenant Compliance

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

+ References

+ Details

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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