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Associate Benefit Plans (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Aug. 29, 2020 | Aug. 31, 2019 | Sep. 01, 2018 | Aug. 29, 2015 | Jan. 14, 2015 | Jan. 06, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Plan shares authorized | 5,217 |  |  |  |  |
Shares reserved for issuance under plan | 2,132 |  |  |  |  |
Associate Stock Purchase Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Plan shares authorized |  |  |  | 1,500 | 1,150 | 800
Shares reserved for issuance under plan | 54 |  |  |  |  |
Maximum number of shares available for purchase per qualified associate | 5 |  |  |  |  |
Associate purchase price as percent of closing price | 90.00% |  |  |  |  |
Shares purchased by qualified associates | 69 | 64 |  |  |  |
Share price | $ 59.71 | $ 71.65 |  |  |  |
Savings Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Company contributions to savings plan | $ 5,491,000 | $ 8,439,000 | $ 7,730,000 |  |  |
Stock Options [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Unrecognized share-based compensation cost | $ 3,700,000 |  |  |  |  |
Unrecognized share-based compensation weighted average period | 1 year 4 months 24 days |  |  |  |  |
Vesting period | 4 years |  |  |  |  |
Expiration period | 7 years |  |  |  |  |
Total intrinsic value of options exercised | $ 2,604,000 | 1,882,000 | 7,516,000 |  |  |
Performance Share Units [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Unrecognized share-based compensation cost | $ 1,536,000 |  |  |  |  |
Unrecognized share-based compensation weighted average period | 2 years 2 months 12 days |  |  |  |  |
Vesting period | 3 years |  |  |  |  |
Performance Share Units [Member] | Minimum [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting percentage | 0.00% |  |  |  |  |
Performance Share Units [Member] | Maximum [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting percentage | 200.00% |  |  |  |  |
Restricted Share Awards [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Fair value of shares vested | $ 1,581,000 | $ 3,368,000 | $ 7,222,000 |  |  |
Unrecognized share-based compensation cost | 0 |  |  |  |  |
Restricted Stock Units [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Unrecognized share-based compensation cost | $ 26,623,000 |  |  |  |  |
Unrecognized share-based compensation weighted average period | 2 years 8 months 12 days |  |  |  |  |

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