Debt Covenant, Specified Maximum Leverage Ratio

No definition available.

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Namespace Prefix:	jack_
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- Definition

Line of Credit Issued

+ References

No definition available.

+ Details

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Namespace Prefix:	jack_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

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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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Indebtedness (Narrative) (Details) - USD ($)	3 Months Ended
Indebtedness (Narrative) (Details) - USD ($)	Apr. 14, 2024	Sep. 28, 2025	Sep. 29, 2024	Mar. 08, 2022	Feb. 11, 2022	Oct. 31, 2021
Debt Instrument [Line Items]
Debt issuance costs		$ 11,890,000	$ 16,225,000
Line of Credit \| Del Taco \| Syndicated Credit Facility
Debt Instrument [Line Items]
Principal amount				$ 75,000,000
Series 2022 Class A-2 Notes \| Senior Notes
Debt Instrument [Line Items]
Principal amount					$ 550,000,000
Total debt						$ 570,700,000
Loss on extinguishment of debt	$ (5,600,000)
Class A-2-II Notes \| Senior Notes
Debt Instrument [Line Items]
Principal amount					550,000,000
Series 2022-1 Class A-1 Notes \| Senior Notes
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity					$ 150,000,000
Series 2022-1 Variable Funding Notes, variable interest rate of 6.788% at September 28, 2025 \| Senior Notes
Debt Instrument [Line Items]
Interest rate		6.788%
Revolving credit facility		$ 0	6,000,000
Unused borrowing capacity		96,800,000
Line of credit issued		$ 53,200,000
Series 2022 Class A-2 Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate		4.476%
Total debt		$ 262,625,000	265,375,000
Effective interest rate		4.851%
Series 2019-1 Class A-2-III Notes \| Senior Notes
Debt Instrument [Line Items]
Effective interest rate		5.258%
Series 2022-1 3.445% Fixed Rate Class A-2-I Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate		3.445%			3.445%
Total debt		$ 511,500,000	522,500,000
Effective interest rate		3.796%
Series 2022-1 4.136% Fixed Rate Class A-2-II Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate		4.136%			4.136%
Total debt		$ 511,500,000	$ 522,500,000
Effective interest rate		4.347%
Series 2019 Class A-2 Notes \| Senior Notes
Debt Instrument [Line Items]
Debt issuance costs					$ 17,400,000
Specified maximum leverage ratio		5.0