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Introduction and Basis of Presentation (Details)	Sep. 24, 2025 restaurant
Franchisor Disclosure [Line Items]
Number of restaurants	1,537
Denny's Brand
Franchisor Disclosure [Line Items]
Number of restaurants	1,459
Keke's
Franchisor Disclosure [Line Items]
Number of restaurants	78
Franchised/licensed Restaurants
Franchisor Disclosure [Line Items]
Number of restaurants	1,452
Franchised/licensed Restaurants | Denny's Brand
Franchisor Disclosure [Line Items]
Number of restaurants	1,397
Franchised/licensed Restaurants | Keke's
Franchisor Disclosure [Line Items]
Number of restaurants	55
Company Restaurants
Franchisor Disclosure [Line Items]
Number of restaurants	85
Company Restaurants | Denny's Brand
Franchisor Disclosure [Line Items]
Number of restaurants	62
Company Restaurants | Keke's
Franchisor Disclosure [Line Items]
Number of restaurants	23

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