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. 20, 2019	Jan. 21, 2018
Average Shares Outstanding [Line Items]
Weighted-average shares outstanding – basic	25,907	29,551
Weighted-average shares outstanding - diluted	26,128	29,853
Excluded from diluted weighted-average shares outstanding, Antidilutive	186	90
Excluded from Diluted Weighted-Average Shares, Performance Conditions Not Satisfied	89	74
Nonvested stock awards and units
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities	208	229
Stock options
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities	11	64
Performance share awards
Average Shares Outstanding [Line Items]
Effect of potentially dilutive securities	2	9

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
-Section 45
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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

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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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