Summary of Refranchisings and Franchise Acquisitions (Summary Of Refranchisings And Franchise Acquisitions) (Details) $ in Thousands	12 Months Ended
Sep. 29, 2024 USD ($) restaurant	Oct. 01, 2023 USD ($) restaurant	Oct. 02, 2022 USD ($) restaurant
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Proceeds from the sale of company-operated restaurants	$ 19,400	$ 85,221	$ 6,391
Gains on the sale of company-operated restaurants	(185)	8,171	30,533
Operating restaurant impairment charges	8,008	4,569	$ 5,927
Del Taco
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Operating restaurant impairment charges	$ 2,600	$ 4,400
Entity Operated Units
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Restaurants sold to Jack in the Box franchisees \| restaurant	0	5	15
Proceeds from the sale of company-operated restaurants	$ 19,400	$ 85,221	$ 6,391
Broker commissions	0	(1,614)	0
Net assets sold (primarily property and equipment)	(5,310)	(17,101)	(1,565)
Goodwill related to the sale of company-operated restaurants	(6,835)	(35,544)	(948)
Franchise fees	(1,266)	(3,086)	0
Sublease liabilities, net	(140)	(8,559)	0
Lease termination	(225)	(393)	0
Other	(2,369)	(926)	0
Gains on the sale of company-operated restaurants	3,255	17,998	3,878
Proceeds from the extension of franchise and lease agreements from the sale of restaurants in prior years	1,500	$ 900	$ 1,400
Operating restaurant impairment charges	$ 2,200
Entity Operated Units \| Del Taco
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Restaurants sold to Jack in the Box franchisees \| restaurant	47	111	0

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

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Increase (Decrease) in Sublease Liabilities

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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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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Amount of gain (loss) on termination of lease before expiration of lease term.

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Amount of divestiture of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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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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