Goodwill And Intangible Assets, Net (Changes In Carrying Amount Of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 30, 2012
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 148,988	$ 140,622
Acquisition of franchised restaurants	256	9,169	36,084
Total goodwill disposals		(174)
Sale of company-operated restaurants to franchisees	(170)	(629)	(1,334)
Goodwill, ending balance	149,074	148,988	140,622
Jack In The Box [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	48,391	47,847
Acquisition of franchised restaurants	256	1,173
Total goodwill disposals		0
Sale of company-operated restaurants to franchisees	(170)	(629)
Goodwill, ending balance	48,477	48,391
Qdoba [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	100,597	92,775
Acquisition of franchised restaurants	0	7,996
Total goodwill disposals		(174)
Sale of company-operated restaurants to franchisees	0	0
Goodwill, ending balance	$ 100,597	$ 100,597