Segment Reporting (Summarized Financial Information Of Reportable Segments) (Details) - USD ($) $ in Thousands	4 Months Ended
Jan. 22, 2017	Jan. 17, 2016	Oct. 02, 2016
Segment Reporting Information [Line Items]
Consolidated revenues	$ 487,933	$ 470,823
Consolidated earnings from operations	73,117	62,514
Gains on the sale of company-operated restaurants	137	818
Interest expense, net	12,717	8,175
Earnings from continuing operations and before income taxes	60,400	54,339
Consolidated depreciation expense	27,755	28,286
Consolidated goodwill	166,045		$ 166,046
Total goodwill disposals	1
Jack in the box brand restaurant operations [Member]
Segment Reporting Information [Line Items]
Gains on the sale of company-operated restaurants	137	818
Consolidated goodwill	48,414		48,415
Total goodwill disposals	1
Qdoba brand restaurant operations [Member]
Segment Reporting Information [Line Items]
Consolidated goodwill	117,631		$ 117,631
Total goodwill disposals	0
Operating Segments [Member] \| Jack in the box brand restaurant operations [Member]
Segment Reporting Information [Line Items]
Consolidated revenues	353,181	347,583
Consolidated earnings from operations	92,404	85,690
Consolidated depreciation expense	19,289	20,473
Operating Segments [Member] \| Qdoba brand restaurant operations [Member]
Segment Reporting Information [Line Items]
Consolidated revenues	134,752	123,240
Consolidated earnings from operations	8,732	8,737
Consolidated depreciation expense	6,492	5,588
Corporate, Non-Segment [Member] \| Shared services and unallocated costs [Member]
Segment Reporting Information [Line Items]
Consolidated earnings from operations	(28,156)	(32,731)
Consolidated depreciation expense	1,974	2,225
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Gains on the sale of company-operated restaurants	137	818
Interest expense, net	$ 12,717	$ 8,175

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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