Summary Of Refranchisings, Franchisee Development And Acquisitions (Purchase Price Allocations On Franchise Acquisitions) (Details) $ in Thousands	12 Months Ended
	Sep. 27, 2015 USD ($) restaurant	Sep. 28, 2014 USD ($) restaurant	Sep. 29, 2013 USD ($) restaurant
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Restaurants acquired from franchisees (restaurants) | restaurant			14
Property and equipment	$ 646	$ 1,398	$ 3,030
Reacquired franchise rights	0	96	148
Goodwill	0	256	9,169
Gains on the acquisition of franchise-operated restaurants	(33)	0	0
Liabilities assumed	(613)	0	(283)
Business Combination, Consideration Transferred	$ 0	$ 1,750	$ 12,064
Jack in the box brand restaurant operations [Member]
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Restaurants acquired from franchisees (restaurants) | restaurant	7	4	1
Goodwill		$ 256
Qdoba brand restaurant operations [Member]
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items]
Restaurants acquired from franchisees (restaurants) | restaurant			13
Goodwill		$ 0