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General liability and workers' comp estimated claims to be paid on the Company's behalf by our insurance providers

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Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for advertising of the entity's goods and services.

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Amount of expense for amortization of capitalized computer software costs.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of impairment loss from 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 total expense recognized in the period for promotion, public relations, and brand or product advertising.

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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.

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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.

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Represents the number of restaurants.

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Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Nature of Operations and Summary of Significant Accounting Policies (Narrative) (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Jul. 07, 2024 USD ($)	Sep. 29, 2024 USD ($) restaurant segment reporting_unit	Oct. 01, 2023 USD ($)	Oct. 02, 2022 USD ($) restaurant
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Restricted cash		$ 29,422	$ 28,254
Capitalized software implementation costs		11,100	7,900
Amortization expense for software implementation costs		4,500	5,000	$ 5,100
Depreciation		$ 59,200	61,700	55,800
Number of operating segments \| segment		2
Goodwill impairment		$ 162,624	0	0
Number of reporting units \| reporting_unit		2
Deferred gift card income		$ 0	19,397
Amounts recognized on unredeemed gift card balances		800	1,600	$ 700
General liability and workers' comp estimated claims to be paid by insurance providers		$ 27,900	$ 31,300
Contractual contributions		5.00%	5.00%	5.00%
Marketing and advertising expense		$ 35,000	$ 38,900	$ 32,600
Del Taco
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Goodwill impairment	$ (162,600)	162,624
Accrued advertising costs		$ (800)	800
Del Taco \| Entity Operated Units
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| restaurant		133
Del Taco \| Franchised Units
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| restaurant		461
Jack in the Box
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| restaurant				9
Goodwill impairment		$ 0
Accrued advertising costs		$ 800	$ 9,500
Jack in the Box \| Entity Operated Units
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| restaurant		150
Jack in the Box \| Franchised Units
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants \| restaurant		2,041
Sales Concentration Risk \| Revenue Benchmark \| Del Taco
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		4.00%	4.00%	4.00%
Other Assets
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Cash surrender value of life insurance		$ 129,700	$ 113,200
Accrued Liabilities
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Deferred gift card income		$ 2,700	$ 2,900
Minimum
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment assigned lives		1 year
Maximum
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment assigned lives		35 years