BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Impairment of Property and Equipment and ROU Assets (Details) $ in Millions	3 Months Ended
Mar. 27, 2024 USD ($)	Mar. 29, 2023 USD ($) restaurant
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Asset impairment charges	$ 0.0
Maximum
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Asset impairment charges		$ 0.1
Closed-store reserve expense	$ 0.1	$ 0.1
California
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Number of restaurants with ROU asset impairment charges \| restaurant		1

Basis of presentation and summary of significant accounting policies.

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- Definition

The number of restaurants with ROU assets with impairment charges.

+ References

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482130/360-10-45-4

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- Definition

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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