Summary of Refranchisings and Franchise Acquisitions (Summary Of Refranchisings And Franchise Acquisitions) (Details) $ in Thousands	12 Months Ended
Oct. 01, 2023 USD ($) restaurant	Oct. 02, 2022 USD ($) restaurant	Oct. 03, 2021 USD ($) restaurant
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Proceeds from the sale of company-operated restaurants	$ 85,221	$ 6,391	$ 1,827
Goodwill related to the sale of company-operated restaurants	(72)	(948)
Gains on the sale of company-operated restaurants	8,171	30,533	$ 6,888
Del Taco
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Goodwill related to the sale of company-operated restaurants	$ 0	$ 0
Entity Operated Units
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Restaurants sold to Jack in the Box franchisees \| restaurant	5	15	0
Proceeds from the sale of company-operated restaurants	$ 85,221	$ 6,391	$ 1,827
Net assets sold (primarily property and equipment)	(17,101)	(1,565)	0
Goodwill related to the sale of company-operated restaurants	(35,544)	(948)	0
Other	(926)	0	2,376
Gains on the sale of company-operated restaurants	17,998	3,878	4,203
Proceeds from the extension of franchise and lease agreements from the sale of restaurants in prior years	900	1,400	1,800
Payments for Commissions	(1,614)	0	0
Franchisor Costs	(3,086)	0	0
Increase (Decrease) in Sublease Liabilities	(8,559)	0	0
Gain (Loss) on Termination of Lease	$ (393)	$ 0	$ 0
Entity Operated Units \| Del Taco
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Restaurants sold to Jack in the Box franchisees \| restaurant	111	0	0

Additional Proceeds From Divestiture Of Businesses And Interests In Affiliates From Prior Years

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Contingency Adjustments From Divestiture Of Businesses And Interests In Affiliates From Prior Years

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Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items].

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Aggregate costs incurred that are directly related to activities, including but not limited to, generating franchise revenues from franchisor owned outlets and franchised outlets.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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The cash inflow associated with the amount received from the sale of a business segment or subsidiary or sale of an entity that is related to it but not strictly controlled during the period (for example, an unconsolidated subsidiary, affiliate, joint venture or equity method investment).

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Amount of divestiture of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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The number of franchises sold during the period when there are significant changes in franchisor-owned outlets or franchised outlets during the period.

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