DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 29, 2025 USD ($) restaurant state	Jun. 29, 2025 USD ($) segment restaurant state	Dec. 29, 2024 USD ($)
Change in Accounting Estimate [Line Items]
Number of restaurants \| restaurant	260	260
Number of states \| state	22	22
Number of restaurants opened \| restaurant	9	14
Operating segments \| segment		1
Reportable segments \| segment		1
Accounts receivable	$ 6,669	$ 6,669	$ 5,034
Restricted cash associated with letters of credit	4,100	4,100
Credit Card Processors
Change in Accounting Estimate [Line Items]
Accounts receivable	$ 5,400	$ 5,400	$ 2,300

Number Of Restaurants Opened

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Restricted Cash, Noncurrent, Associated With Letters of Credit

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- Definition

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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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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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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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Represents the number of restaurants.

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The number of states the entity operates in as of the balance sheet date.

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