Variable Interest Entities ("VIEs") (Components Of FFE's Balance Sheet) (Details) (USD $) In Thousands, unless otherwise specified	Apr. 15, 2012		Oct. 02, 2011
Variable Interest Entity [Line Items]
Other current assets	$ 1,139		$ 1,793
Current liabilities	258,211		282,983
Other long-term liabilities	293,642		290,723
Retained earnings	1,096,602		1,063,020
Total liabilities and stockholders' equity	1,460,808		1,432,322
Jack In The Box Franchise Finance, LLC ("FFE") [Member]
Variable Interest Entity [Line Items]
Cash	165		531
Other current assets	2,330	[1]	2,086	[1]
Other assets, net	13,077	[1]	12,292	[1]
Total assets	15,572		14,909
Current liabilities	470		140
Revolving credit facility	0		1,160
Other long-term liabilities	15,608	[2]	14,046	[2]
Retained earnings	(506)		(437)
Total liabilities and stockholders' equity	$ 15,572		$ 14,909

[1] Consists primarily of amounts due from franchisees.

[2] Consists primarily of the capital note contributions from Jack in the Box which are eliminated in consolidation.