Summary of Refranchisings and Franchise Acquisition (Summary Of Refranchisings And Franchise Acquisitions) (Details) $ in Thousands	12 Months Ended
Sep. 28, 2025 USD ($) restaurant	Sep. 29, 2024 USD ($) restaurant	Oct. 01, 2023 USD ($) restaurant
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Proceeds from the sale of company-operated restaurants	$ 6,384	$ 19,400	$ 85,221
Goodwill related to the sale of company-operated restaurants		(5,544)
Gains on the sale of company-operated restaurants	(2,161)	(185)	8,171
Impairment of trademark	(4,384)	(8,008)	(4,569)
Del Taco
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Goodwill related to the sale of company-operated restaurants		(5,544)
Impairment of trademark	$ (2,400)	$ (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	1	0	5
Proceeds from the sale of company-operated restaurants	$ 6,384	$ 19,400	$ 85,221
Broker commissions	0	0	(1,614)
Net assets sold (primarily property and equipment)	(1,883)	(5,310)	(17,101)
Goodwill related to the sale of company-operated restaurants	(461)	(6,835)	(35,544)
Franchise fees	(364)	(1,266)	(3,086)
Sublease liabilities, net	0	(140)	(8,559)
Lease termination	(217)	(225)	(393)
Other	(216)	(2,369)	(926)
Gains on the sale of company-operated restaurants	3,243	3,255	17,998
Proceeds from the extension of franchise and lease agreements from the sale of restaurants in prior years	$ 700	1,500	$ 900
Impairment of trademark		$ 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	13	47	111

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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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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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