Revenue - Additional Information (Detail)	4 Months Ended
Apr. 21, 2018 USD ($) Commissary	Dec. 30, 2017 USD ($)
Disaggregation Of Revenue [Line Items]
Revenue recognition performance obligation on international shipments	$ 0
Revenue recognition performance obligation	$ 0
Revenue, performance obligation, description of good or service	The Company does not receive pre-payment from its customers, or enter into commitments to provide goods or services that have terms greater than one year
Revenue recognition payment terms	30 days
Contract assets	$ 0	$ 0
Minimum [Member]
Disaggregation Of Revenue [Line Items]
Revenue recognition contract terms	1 year
Maximum [Member]
Disaggregation Of Revenue [Line Items]
Revenue performance obligation contract expected term	1 year
Expected amortization period of asset	1 year
Manufacturers/brokers supplying DeCA [Member]
Disaggregation Of Revenue [Line Items]
Number of commissaries \| Commissary	237

Expected amortization period of asset.

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- Definition

Number of commissaries.

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- Definition

Revenue performance obligation contract expected term.

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- Definition

Revenue recognition contract terms.

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- Definition

Revenue recognition payment terms.

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- Definition

Revenue recognition performance obligation.

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No definition available.

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- Definition

Revenue recognition performance obligation on international shipments.

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173487&loc=SL51747714-108306

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130549-203045

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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.

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- Definition

Description of good or service to be transferred in contract with customer. Includes, but is not limited to, arrangement for another party to transfer good or service to customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130554-203045

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