Variable Interest Entities (Components Of FFE's Balance Sheet) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012		Oct. 02, 2011
Variable Interest Entity [Line Items]
Other current assets	$ 375		$ 1,793
Current liabilities	275,302		282,983
Other long-term liabilities	371,202		290,723
Retained earnings	1,120,671		1,063,020
Total liabilities and stockholders' equity	1,463,725		1,432,322
Jack In The Box Franchise Finance, LLC ("FFE") [Member]
Variable Interest Entity [Line Items]
Cash	444		531
Other current assets	2,536	[1]	2,086	[1]
Other assets, net	11,051	[1]	12,292	[1]
Total assets	14,031		14,909
Current liabilities	14		140
Revolving credit facility	0		1,160
Other long-term liabilities	14,428	[2]	14,046	[2]
Retained earnings	(411)		(437)
Total liabilities and stockholders' equity	$ 14,031		$ 14,909

[1] Consists primarily of amounts due from franchisees.

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