XML 66 R50.htm IDEA: XBRL DOCUMENT
v3.21.1

Contingencies and Legal Matters (Details) $ in Thousands | 1 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Aug. 31, 2010 former_employee | Apr. 11, 2021 USD ($) | Sep. 27, 2020 USD ($)
Loss Contingencies [Line Items] |  |  |
Accrual of loss contingency |  | $ 3,900 | $ 3,800
Lease guarantee |  | $ 26,400 |
Qdoba guaranteed leases, remaining term |  | 15 years |
Gessele v. Jack in the Box Inc. |  |  |
Loss Contingencies [Line Items] |  |  |
Number of former employees | former_employee | 5 |  |

X
- Definition Lessee, Guaranteed Leases, Remaining Term + References No definition available. + Details
Name: | jack_LesseeGuaranteedLeasesRemainingTerm
Namespace Prefix: | jack_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of Former Employees + References No definition available. + Details
Name: | jack_NumberOfFormerEmployees
Namespace Prefix: | jack_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments. + References No definition available. + Details
Name: | us-gaap_ContractualObligation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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. + References No definition available. + Details
Name: | us-gaap_LossContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of loss contingency liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
Name: | us-gaap_LossContingencyAccrualAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | srt_LitigationCaseAxis=jack_GesseleVJackInTheBoxIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |