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Average Shares Outstanding (Reconciliation of Basic Weighted-Average Shares Outstanding to Diluted Weighted-Average Shares Outstanding) (Details) - shares shares in Thousands	12 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 30, 2018
Average Shares Outstanding [Line Items]
Weighted-average shares outstanding - basic (in shares)	23,125	25,823	28,499
Weighted-average shares outstanding - diluted (in shares)	23,269	26,068	28,807
Antidilutive (in shares)	318	186	150
Performance conditions not satisfied at the end of the period (in shares)	14	65	44
Nonvested stock awards and units
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities (in shares)	137	211	240
Stock options
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities (in shares)	0	10	40
Performance share awards
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities (in shares)	7	24	28

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Average shares outstanding line items

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

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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

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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.

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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.

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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.

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