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Introduction and Basis of Reporting (Narrative) (Details)	12 Months Ended
	Dec. 25, 2019 country territory restaurant state	Dec. 26, 2018 restaurant	Dec. 27, 2017 restaurant	Dec. 28, 2016 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	12
Number of restaurants	1,703	1,709	1,735
California
Franchisor Disclosure [Line Items]
Percentage of restaurants operated by geographic region	23.00%
Texas
Franchisor Disclosure [Line Items]
Percentage of restaurants operated by geographic region	12.00%
Florida
Franchisor Disclosure [Line Items]
Percentage of restaurants operated by geographic region	8.00%
Franchise
Franchisor Disclosure [Line Items]
Number of restaurants	1,635	1,536	1,557	1,564
Company-owned restaurants
Franchisor Disclosure [Line Items]
Number of restaurants	68	173	178	169

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Number of Territories in which Entity Operates

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