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Introduction and Basis of Presentation (Details)	Jun. 28, 2023 restaurant
Franchisor Disclosure [Line Items]
Number of restaurants	1,646
Denny's Brand
Franchisor Disclosure [Line Items]
Number of restaurants	1,591
Keke's
Franchisor Disclosure [Line Items]
Number of restaurants	55
Franchised/licensed Restaurants
Franchisor Disclosure [Line Items]
Number of restaurants	1,572
Franchised/licensed Restaurants | Denny's Brand
Franchisor Disclosure [Line Items]
Number of restaurants	1,525
Franchised/licensed Restaurants | Keke's
Franchisor Disclosure [Line Items]
Number of restaurants	47
Company Restaurants
Franchisor Disclosure [Line Items]
Number of restaurants	74
Company Restaurants | Denny's Brand
Franchisor Disclosure [Line Items]
Number of restaurants	66
Company Restaurants | Keke's
Franchisor Disclosure [Line Items]
Number of restaurants	8

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