Goodwill and Intangible Assets - (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 27, 2023	Dec. 28, 2022	Dec. 29, 2021
Finite-Lived Intangible Assets [Line Items]
Amortization expense of definite-lived intangible assets and other assets	$ 2,200	$ 2,000	$ 2,100
Goodwill impairment charges	$ 6,363	$ 0	$ 0
Franchise agreements
Finite-Lived Intangible Assets [Line Items]
Weighted average useful life	14 years
Reacquired franchise rights
Finite-Lived Intangible Assets [Line Items]
Weighted average useful life	6 years
Impairment of franchisee rights	$ 100

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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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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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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