Variable Interest Entities ("VIEs") (Components Of FFE's Balance Sheet) (Details) (USD $) In Thousands, unless otherwise specified	Jan. 22, 2012		Oct. 02, 2011
Variable Interest Entity [Line Items]
Other current assets	$ 1,275		$ 1,793
Current liabilities	246,275		282,983
Other long-term liabilities	296,136		290,723
Retained earnings	1,074,970		1,063,020
Total liabilities and stockholders' equity	1,437,100		1,432,322
Jack In The Box Franchise Finance, LLC ("FFE") [Member]
Variable Interest Entity [Line Items]
Cash	1,250		531
Other current assets	2,164	[1]	2,086	[1]
Other assets, net	12,410	[1]	12,292	[1]
Total assets	15,824		14,909
Current liabilities	234		140
Revolving credit facility	1,886		1,160
Other long-term liabilities	14,226	[2]	14,046	[2]
Retained earnings	(522)		(437)
Total liabilities and stockholders' equity	$ 15,824		$ 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.