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Goodwill And Intangible Assets (Changes in Carrying Amount of Goodwill) (Details) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Sep. 28, 2025	Jul. 06, 2025	Apr. 13, 2025	Jul. 07, 2024	Sep. 28, 2025	Sep. 29, 2024	Oct. 01, 2023
Goodwill [Roll Forward]
Goodwill	$ 330,306				$ 330,306	$ 323,833	$ 329,986
Accumulated impairment losses	(194,280)				(194,280)	(162,624)	0
Goodwill, beginning balance					161,209	329,986
Goodwill, acquired during period					6,326
Impairment of goodwill					(31,656)	(162,624)
Goodwill related to the sale of company-operated restaurants						(5,544)
Reclassified to assets held for sale					147	(609)
Goodwill, ending balance	136,026				$ 136,026	$ 161,209	329,986
Goodwill, Impairment Loss, Statement of Income or Comprehensive Income [Extensible Enumeration]					Impairment of goodwill and intangible assets	Impairment of goodwill and intangible assets
Jack in the Box
Goodwill [Roll Forward]
Goodwill	136,026				$ 136,026	$ 135,827	136,027
Accumulated impairment losses	0				0	0	0
Goodwill, beginning balance					135,827	136,027
Goodwill, acquired during period					0
Impairment of goodwill					0	0
Goodwill related to the sale of company-operated restaurants						0
Reclassified to assets held for sale					199	(200)
Goodwill, ending balance	136,026				136,026	135,827	136,027
Del Taco
Goodwill [Roll Forward]
Goodwill	194,280				194,280	188,006	193,959
Accumulated impairment losses	(194,280)				(194,280)	(162,624)	0
Goodwill, beginning balance					25,382	193,959
Goodwill, acquired during period	6,300	$ 6,300			6,326
Impairment of goodwill			$ (25,300)	$ (162,600)	(31,656)	(162,624)
Goodwill related to the sale of company-operated restaurants						(5,544)
Reclassified to assets held for sale					(52)	(409)
Goodwill, ending balance	$ 0				$ 0	$ 25,382	$ 193,959