Nature Of Operations And Summary Of Significant Accounting Policies (Summary Of Advertising Costs) (Details) (Company-Operated [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 30, 2012
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Advertising costs	$ 60,564	$ 62,862	$ 62,892
Jack In The Box [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Advertising costs	42,349	46,739	49,757
Qdoba [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Advertising costs	$ 18,215	$ 16,123	$ 13,135