Average Shares Outstanding (Reconciliation Of Basic Weighted-Average Shares Outstanding To Diluted Weighted-Average Shares Outstanding) (Details) - shares shares in Thousands	4 Months Ended
Jan. 19, 2020	Jan. 20, 2019
Average Shares Outstanding [Line Items]
Weighted-average shares outstanding – basic	23,741	25,907
Weighted-average shares outstanding - diluted	23,936	26,128
Excluded from diluted weighted-average shares outstanding, Antidilutive	224	186
Excluded from diluted weighted-average shares, performance conditions not satisfied	80	89
Nonvested stock awards and units
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities	181	208
Stock options
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities	7	11
Performance share awards
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities	7	2

Average shares outstanding line items

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- Definition

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

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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.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
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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.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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