Segment Reporting (Summarized Financial Information Of Reportable Segments) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jul. 05, 2015	Jul. 06, 2014	Jul. 05, 2015	Jul. 06, 2014	Sep. 28, 2014
Segment Reporting Information [Line Items]
Consolidated revenues	$ 359,506	$ 348,492	$ 1,186,249	$ 1,139,444
Consolidated earnings from operations	50,395	43,000	155,499	133,083
Interest Income (Expense), Net	4,504	3,535	13,937	12,388
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	45,891	39,465	141,562	120,695
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	(183)	24	(4,353)	2,242
Consolidated depreciation expense	20,174	20,691	67,675	70,020
Consolidated goodwill	149,042		149,042		$ 149,074
Goodwill, Written off Related to Sale of Business Unit	0	(5)	(32)	(134)
Qdoba brand restaurant operations [Member]
Segment Reporting Information [Line Items]
Consolidated revenues	96,167	88,755	301,515	269,794
Consolidated earnings from operations	13,805	9,641	37,265	26,354
Consolidated depreciation expense	3,864	3,893	13,179	13,029
Consolidated goodwill	100,597		100,597		100,597
Goodwill, Written off Related to Sale of Business Unit			0
Jack in the box brand restaurant operations [Member]
Segment Reporting Information [Line Items]
Consolidated revenues	263,339	259,737	884,734	869,650
Consolidated earnings from operations	62,355	54,413	207,523	184,333
Consolidated depreciation expense	14,737	15,110	49,051	51,379
Consolidated goodwill	48,445		48,445		$ 48,477
Goodwill, Written off Related to Sale of Business Unit			(32)
Shared services and unallocated costs [Member]
Segment Reporting Information [Line Items]
Consolidated earnings from operations	(25,582)	(21,078)	(84,936)	(79,846)
Consolidated depreciation expense	1,573	1,688	5,445	5,612
Total gain (loss) on the sale of company-operated restaurants [Member]
Segment Reporting Information [Line Items]
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	(183)	24	$ (4,353)	2,242
Subtotal of gains (losses) on sale of company-operated restaurants [Member]
Segment Reporting Information [Line Items]
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	$ (183)	$ 346		$ 5,679

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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The net amount of operating interest income (expense).

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