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Goodwill And Intangible Assets (Changes in Carrying Amount of Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 01, 2023	Oct. 02, 2022	Oct. 03, 2021
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 366,821	$ 47,774
Goodwill related to the sale of company-operated restaurants	(72)	(948)
Reclassified to assets held for sale			$ (1,291)
Goodwill, ending balance	329,986	366,821	47,774
Jack in the Box
Goodwill [Roll Forward]
Goodwill, acquired during period		273
Goodwill related to the sale of company-operated restaurants	(35,472)
Del Taco
Goodwill [Roll Forward]
Goodwill, acquired during period	319,722	319,722
Goodwill, ending balance	319,722
Jack in the Box
Goodwill [Roll Forward]
Goodwill, beginning balance	136,099	47,774
Goodwill related to the sale of company-operated restaurants	(72)	(948)
Reclassified to assets held for sale	0
Goodwill, ending balance	136,027	136,099	47,774
Jack in the Box \| Jack in the Box
Goodwill [Roll Forward]
Goodwill, acquired during period		273
Goodwill related to the sale of company-operated restaurants	0
Jack in the Box \| Del Taco
Goodwill [Roll Forward]
Goodwill, acquired during period	89,000	89,000
Del Taco
Goodwill [Roll Forward]
Goodwill, beginning balance	230,722	0
Goodwill related to the sale of company-operated restaurants	0	0
Reclassified to assets held for sale		(1,291)
Goodwill, ending balance	193,959	230,722	$ 0
Del Taco \| Jack in the Box
Goodwill [Roll Forward]
Goodwill, acquired during period		0
Goodwill related to the sale of company-operated restaurants	(35,472)
Del Taco \| Del Taco
Goodwill [Roll Forward]
Goodwill, acquired during period	$ 230,722	$ 230,722