Defined Benefit Plan, Net Periodic Benefit Cost Excluding Service Cost

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- Definition

Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]

+ References

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- Definition

Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=65896087&loc=d3e11374-113907

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- Definition

Represents the number of restaurants.

+ References

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Basis Of Presentation (Details) $ in Thousands	9 Months Ended
Basis Of Presentation (Details) $ in Thousands	Jul. 09, 2017 USD ($) restaurant	Jul. 03, 2016 USD ($) restaurant	Oct. 02, 2016 USD ($)
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Excess Tax Benefit from Share-based Compensation, Financing Activities \| $	$ 4,133	$ 3,822
Defined Benefit Plan, Net Periodic Benefit Cost Excluding Service Cost \| $	$ 1,600	$ 6,300
Current Maturities of Long-Term Debt [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Unamortized Debt Issuance Expense \| $			$ 1,600
Long-Term Debt, Net of Current Maturities [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Unamortized Debt Issuance Expense \| $			2,200
Term Loan [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Unamortized Debt Issuance Expense \| $			$ 3,800
Jack in the box brand restaurant operations [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	2,255	2,254
Jack in the box brand restaurant operations [Member] \| Entity Operated Units [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	340	415
Jack in the box brand restaurant operations [Member] \| Franchised Units [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	1,915	1,839
Qdoba brand restaurant operations [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	720	688
Qdoba brand restaurant operations [Member] \| Entity Operated Units [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	381	344
Qdoba brand restaurant operations [Member] \| Franchised Units [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	339	344
Discontinued Operations [Member] \| 2013 Qdoba Closures [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	62