Document And Entity Information	9 Months Ended
	Jul. 07, 2013	Aug. 02, 2013
Document And Entity Information [Abstract]
Entity Registrant Name	JACK IN THE BOX INC /NEW/
Entity Central Index Key	0000807882
Current Fiscal Year End Date	--09-29
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Jul. 07, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		43,301,720