Segment Reporting (Summarized Financial Information Of Reportable Segments) (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Jul. 10, 2011	Jul. 04, 2010	Jul. 10, 2011	Jul. 04, 2010
Distribution operations, revenues	$ 125,704	$ 94,039	$ 393,753	$ 289,419
Consolidated revenues	519,279	523,294	1,689,129	1,734,318
Distribution operations and other, earnings	(245)	(606)	(1,599)	(1,477)
Consolidated earnings from operations	32,953	41,848	101,658	116,729
Jack In The Box [Member]
Revenues by segment	337,980	388,649	1,135,626	1,323,259
Consolidated earnings from operations	28,500	39,097	95,675	110,342
Qdoba [Member]
Revenues by segment	55,595	40,606	159,750	121,640
Consolidated earnings from operations	$ 4,698	$ 3,357	$ 7,582	$ 7,864

The net result for the period of deducting operating expenses from operating revenues.

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- Definition

Other costs incurred during the reporting period related to other revenue generating activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 2

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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- Definition

Revenues from the sale of other goods or rendering of other services, not elsewhere specified in the taxonomy; net of (reduced by) sales adjustments, returns, allowances, and discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 1

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a),(d))
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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- Definition

Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 1

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

+ Details

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- Definition

Amount of total revenue for the reportable segments, including revenue from external customers, transactions with other operating segments of the same entity, and (gross) interest revenue. All considered to be "operating revenue" for purposes of the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 27
-Subparagraph a, b, c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (a),(b),(c)
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8736-108599

+ Details

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