Segment Reporting (Summarized Financial Information Of Reportable Segments) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jul. 09, 2017	Jul. 03, 2016	Jul. 09, 2017	Jul. 03, 2016	Oct. 02, 2016
Segment Reporting Information [Line Items]
Consolidated revenues	$ 357,846	$ 368,938	$ 1,215,168	$ 1,200,912
Consolidated earnings from operations	66,981	55,705	205,748	171,005
Gains on the sale of company-operated restaurants	13,250	409	21,166	1,224
Interest expense, net	11,433	7,613	35,091	22,699
Consolidated earnings from continuing operations and before income taxes	55,548	48,092	170,657	148,306
Consolidated depreciation expense	20,214	20,814	68,999	69,748
Sale of company-operated restaurants to franchisees			(4,795)
Acquisition of franchise-operated restaurants			11,712
Goodwill	172,963		172,963		$ 166,046
Jack in the box brand restaurant operations [Member]
Segment Reporting Information [Line Items]
Gains on the sale of company-operated restaurants	13,250	409	21,166	1,224
Sale of company-operated restaurants to franchisees			(4,795)
Acquisition of franchise-operated restaurants	1,891	0	11,712
Goodwill	55,332		55,332		48,415
Qdoba brand restaurant operations [Member]
Segment Reporting Information [Line Items]
Sale of company-operated restaurants to franchisees			0
Acquisition of franchise-operated restaurants			0
Goodwill	117,631		117,631		$ 117,631
Operating Segments [Member] \| Jack in the box brand restaurant operations [Member]
Segment Reporting Information [Line Items]
Consolidated revenues	246,101	264,493	865,166	876,138
Consolidated earnings from operations	59,423	69,528	220,485	218,364
Consolidated depreciation expense	13,731	14,877	47,503	50,409
Operating Segments [Member] \| Qdoba brand restaurant operations [Member]
Segment Reporting Information [Line Items]
Consolidated revenues	111,745	104,445	350,002	324,774
Consolidated earnings from operations	11,905	14,172	29,126	33,532
Consolidated depreciation expense	4,875	4,536	16,274	14,403
Corporate, Non-Segment [Member] \| Shared services and unallocated costs [Member]
Segment Reporting Information [Line Items]
Consolidated earnings from operations	(17,597)	(28,404)	(65,029)	(82,115)
Consolidated depreciation expense	1,608	1,401	5,222	4,936
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Gains on the sale of company-operated restaurants	13,250	409	21,166	1,224
Interest expense, net	$ 11,433	$ 7,613	$ 35,091	$ 22,699

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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