XML 51 R39.htm IDEA: XBRL DOCUMENT
v3.5.0.2

Summary Of Refranchisings, Franchisee Development And Acquisitions (Purchase Price Allocations On Franchise Acquisitions) (Details) - restaurant | 9 Months Ended
--- | ---
Jul. 03, 2016 | Jul. 05, 2015
Jack in the box brand restaurant operations [Member] |  |
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items] |  |
Significant Changes, Franchises Purchased During Period | 1 | 7

X
- Definition Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]. + References No definition available. + Details
Name: | jack_SummaryOfRefranchisingsFranchiseeDevelopmentAndAcquisitionsLineItems
Namespace Prefix: | jack_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of franchises purchased during the period when there are significant changes in franchisor-owned outlets or franchised outlets during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 952 -SubTopic 605 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68064525&loc=d3e68639-108044 + Details
Name: | us-gaap_SignificantChangesFranchisesPurchasedDuringPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=jack_JackintheboxbrandrestaurantoperationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |