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Introduction and Basis of Presentation (Details)	Sep. 25, 2024 restaurant
Franchisor Disclosure [Line Items]
Number of restaurants	1,586
Denny's Brand
Franchisor Disclosure [Line Items]
Number of restaurants	1,525
Keke's
Franchisor Disclosure [Line Items]
Number of restaurants	61
Franchised/licensed Restaurants
Franchisor Disclosure [Line Items]
Number of restaurants	1,514
Franchised/licensed Restaurants | Denny's Brand
Franchisor Disclosure [Line Items]
Number of restaurants	1,464
Franchised/licensed Restaurants | Keke's
Franchisor Disclosure [Line Items]
Number of restaurants	50
Company Restaurants
Franchisor Disclosure [Line Items]
Number of restaurants	72
Company Restaurants | Denny's Brand
Franchisor Disclosure [Line Items]
Number of restaurants	61
Company Restaurants | Keke's
Franchisor Disclosure [Line Items]
Number of restaurants	11

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