Document And Entity Information	6 Months Ended
	Apr. 12, 2015	May 08, 2015
Document And Entity Information [Abstract]
Entity Registrant Name	JACK IN THE BOX INC /NEW/
Entity Central Index Key	0000807882
Current Fiscal Year End Date	--09-27
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Apr. 12, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q2
Amendment Flag	true
Amendment Description	The amendment is being filed solely to correct the allocation of total depreciation expense by segment noted in a table in footnote 14 Segment Reporting. The depreciation amounts for the Qdoba restaurant operations segment and Shared services and allocated costs caption for the quarter and year-to-date 2015 periods were inadvertently transposed in the original filing.
Entity Common Stock, Shares Outstanding		37,380,529