Nature Of Operations And Summary Of Significant Accounting Policies (Narrative) (Details) $ in Thousands	12 Months Ended
Oct. 01, 2017 USD ($) restaurant	Oct. 02, 2016 USD ($) restaurant	Sep. 27, 2015 USD ($) restaurant
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Assets held for sale and leaseback	$ 15,792	$ 14,259
Assets Held-for-sale, Not Part of Disposal Group, Other	8,315	0
Assets Held-for-sale, Not Part of Disposal Group, Current	24,107	14,259
Depreciation	88,210	92,082	$ 88,778
Revenue recognized on unredeemed gift cards	1,200	1,000	$ 1,000
General liability and workers' comp estimated claims to be paid by insurance providers	$ 3,900	$ 8,600
Fiscal Year	52	53	52
Franchise rental agreement period	P20Y
Excess Tax Benefit from Share-based Compensation, Financing Activities	$ 4,232	$ 7,461	$ 18,602
Defined Benefit Plan, Net Periodic Benefit Cost Excluding Service Cost	2,000	8,200
Other Assets [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Cash Surrender Value of Life Insurance	110,100	106,000
Current Maturities of Long-Term Debt [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Unamortized Debt Issuance Expense	$ 1,502	1,639
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
Minimum [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment assigned lives	1 year
Maximum [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment assigned lives	35 years
Jack in the box brand restaurant operations [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of Restaurants \| restaurant	2,251	2,255	2,249
Marketing funds including contractual contributions	5.00%	5.00%	5.00%
Qdoba brand restaurant operations [Member]
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of Restaurants \| restaurant	726	699	661
Marketing funds including contractual contributions	1.30%	2.00%	2.00%

Costs for new and existing restaurants that we plan to sell and leaseback within the next year.

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Contractual Contributions Towards Advertising Costs Percentage Of Sales

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Defined Benefit Plan, Net Periodic Benefit Cost Excluding Service Cost

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Fiscal Year

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General liability and workers' comp estimated claims to be paid on the Company's behalf by our insurance providers

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Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

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Amount of other assets held-for-sale that are not part of a disposal group.

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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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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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.

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Represents the number of restaurants.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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The amount of breakage recognized related to unredeemed gift cards. Breakage occurs when a customer pays in advance of vendor performance and does not demand full performance for various reasons.

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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.

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