Goodwill And Intangible Assets (Changes in Carrying Amount of Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
Oct. 02, 2022	Oct. 03, 2021
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 47,774	$ 47,161
Goodwill, acquired during period		613
Sale of Jack in the Box company-operated restaurants to franchisees		(948)
Goodwill, ending balance	366,821	47,774
Jack in the Box
Goodwill [Roll Forward]
Goodwill, acquired during period		273
Del Taco
Goodwill [Roll Forward]
Goodwill, acquired during period	319,722
Goodwill, ending balance	319,722
Jack in the Box
Goodwill [Roll Forward]
Goodwill, beginning balance	47,774	47,161
Goodwill, acquired during period		613
Sale of Jack in the Box company-operated restaurants to franchisees		(948)
Goodwill, ending balance	136,099	47,774
Jack in the Box \| Jack in the Box
Goodwill [Roll Forward]
Goodwill, acquired during period		273
Jack in the Box \| Del Taco
Goodwill [Roll Forward]
Goodwill, acquired during period	89,000
Del Taco
Goodwill [Roll Forward]
Goodwill, beginning balance	0	0
Goodwill, acquired during period		0
Sale of Jack in the Box company-operated restaurants to franchisees		0
Goodwill, ending balance	230,722	0
Del Taco \| Jack in the Box
Goodwill [Roll Forward]
Goodwill, acquired during period		$ 0
Del Taco \| Del Taco
Goodwill [Roll Forward]
Goodwill, acquired during period	$ 230,722

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
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-Section 55
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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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