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Introduction and Basis of Reporting - (Narrative) (Details)	12 Months Ended
	Dec. 29, 2021 restaurant country state territory	Dec. 30, 2020 restaurant	Dec. 25, 2019 restaurant	Dec. 26, 2018 restaurant
Franchisor Disclosure [Line Items]
Number of states in which entity operates | state	50
Number of territories in which entity operates | territory	2
Number of foreign countries in which entity operates | country	11
Number of restaurants	1,640	1,650	1,703
Franchise
Franchisor Disclosure [Line Items]
Number of restaurants	1,575	1,585	1,635	1,536
Company-owned restaurants
Franchisor Disclosure [Line Items]
Number of restaurants	65	65	68	173
Geographic Concentration Risk | Geographic Area | California
Franchisor Disclosure [Line Items]
Percentage of restaurants operated by geographic region	23.00%
Geographic Concentration Risk | Geographic Area | Texas
Franchisor Disclosure [Line Items]
Percentage of restaurants operated by geographic region	12.00%
Geographic Concentration Risk | Geographic Area | Florida
Franchisor Disclosure [Line Items]
Percentage of restaurants operated by geographic region	8.00%

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Number of Territories in which Entity Operates

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