BASIS OF PRESENTATION - Narrative (Details) $ in Millions	4 Months Ended
Jan. 19, 2025 USD ($) restaurant reporting_unit segment	Jan. 21, 2024 USD ($)
Net Investment Income [Line Items]
Number of operating segments \| segment	2
Marketing and advertising expense \| $	$ 10.5	$ 10.4
Number of reporting units \| reporting_unit	2
Jack in the Box restaurant operations
Net Investment Income [Line Items]
Contractual obligation (percent)	5.00%	5.00%
Del Taco
Net Investment Income [Line Items]
Contractual obligation (percent)	4.00%
Company operated \| Jack in the Box restaurant operations
Net Investment Income [Line Items]
Number of operating segments	152
Company operated \| Del Taco
Net Investment Income [Line Items]
Number of operating segments	119
Franchise-operated \| Jack in the Box restaurant operations
Net Investment Income [Line Items]
Number of operating segments	2,038
Franchise-operated \| Del Taco
Net Investment Income [Line Items]
Number of operating segments	470

ContractualContributionsTowardsAdvertisingCostsPercentageOfSales [Line Items]

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- Definition

The total expense recognized in the period for promotion, public relations, and brand or product advertising.

+ References

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-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
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-Publisher FASB
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-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
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