Average Shares Outstanding (Reconciliation of Basic Weighted-Average Shares Outstanding to Diluted Weighted-Average Shares Outstanding) (Details) - shares shares in Thousands	12 Months Ended
Oct. 01, 2023	Oct. 02, 2022	Oct. 03, 2021
Average Shares Outstanding [Line Items]
Weighted-average shares outstanding - basic (in shares)	20,603	21,195	22,402
Weighted-average shares outstanding - diluted (in shares)	20,764	21,245	22,478
Antidilutive (in shares)	25	23	29
Performance conditions not satisfied at the end of the period (in shares)	81	61	25
Nonvested stock awards and units
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities (in shares)	134	47	62
Del Taco options subject to accelerated vesting
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities (in shares)	1	1	9
Performance share awards
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities (in shares)	26	2	5

Average shares outstanding line items

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- Definition

Excluded from Diluted Weighted-Average Shares, Performance Conditions Not Satisfied

+ References

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482662/260-10-50-1

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480454/718-10-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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-Section 50
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-URI https://asc.fasb.org//1943274/2147482662/260-10-50-1

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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-URI https://asc.fasb.org//1943274/2147482662/260-10-50-1

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