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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Amount of 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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Amount due the Entity as a result of customers utilizing point of sale debit or credit cards in exchange transactions with the entity which are 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. Generally, only investments with original maturities of three months or less qualify under that definition.

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Duration of a fiscal period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Represents the number of stores.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details) $ in Thousands	12 Months Ended
	Jul. 29, 2017 USD ($) store segment	Jul. 30, 2016 USD ($)	Jul. 25, 2015 USD ($)
Accounting Policies [Abstract]
Number of stores \| store	29
Fiscal period duration	371 days	364 days	364 days
Number of operating segments \| segment	1
Cash and Cash Equivalents [Abstract]
Credit and debit card receivables	$ 7,641	$ 7,534
Inventory Disclosure [Abstract]
Percentage of LIFO inventory	65.00%
LIFO reserve inventory	$ 14,410	14,522
Marketing and Advertising Expense [Abstract]
Advertising expense	$ 11,824	11,644	$ 11,121
Buildings
Property, Plant and Equipment [Line Items]
Useful life	30 years
Store fixtures and equipment
Property, Plant and Equipment [Line Items]
Useful life	10 years
Vehicles
Property, Plant and Equipment [Line Items]
Useful life	3 years
Wakefern
Related Party Transaction [Line Items]
Demand deposits invested at related party Wakefern	$ 60,037	$ 63,609