NATURE OF OPERATIONS (Details)	Jun. 24, 2020 Restaurant Shack
Class of Stock [Line Items]
Number of restaurants	292
United States \| Company-operated
Class of Stock [Line Items]
Number of restaurants	171
Number of Shacks closed \| Shack	8
United States \| Licensed
Class of Stock [Line Items]
Number of restaurants	22
Number of Shacks closed \| Shack	27
Non-United States \| Licensed
Class of Stock [Line Items]
Number of restaurants	99

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.

No definition available.

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