Summary of Refranchisings and Franchise Acquisitions (Purchase Price Allocations on Franchise Acquisitions) (Details) $ in Thousands	12 Months Ended
Oct. 03, 2021 USD ($) restaurant	Sep. 27, 2020 USD ($) restaurant	Sep. 29, 2019 restaurant
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Number of restaurants acquired from franchisees \| restaurant	20	8	0
Goodwill	$ 47,774	$ 47,161
Gains on the acquisition of franchise-operated restaurants	(340)	0
Franchise Acquisitions
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Inventory	258	73
Property and equipment	1,136	903
Intangible assets	245	263
Other assets	10	6
Goodwill	613	414
Liabilities assumed	(277)	(800)
Total consideration	1,645	$ 859
Non-cash consideration	1,300
Receivables eliminated in acquisition accounting	300
Accounts payable recorded in acquisition accounting	$ 1,000

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