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Associate Benefit Plans (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Aug. 31, 2019 | Sep. 01, 2018 | Sep. 02, 2017 | 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 | 2,726 |  |  |  |  |
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 | 124 |  |  |  |  |
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 | 64 | 57 |  |  |  |
Share price | $ 71.65 | $ 78.65 |  |  |  |
Savings Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Company contributions to savings plan | $ 8,439 | $ 7,730 | $ 7,048 |  |  |
Stock Options [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Unrecognized share-based compensation cost | $ 7,697 |  |  |  |  |
Unrecognized share-based compensation weighted average period | 2 years 1 month 6 days |  |  |  |  |
Vesting period | 4 years |  |  |  |  |
Expiration period | 7 years |  |  |  |  |
Total intrinsic value of options exercised | $ 1,882 | 7,516 | 9,474 |  |  |
Restricted Share Awards [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Fair value of shares vested | 3,368 | $ 7,222 | $ 7,357 |  |  |
Unrecognized share-based compensation cost | $ 266 |  |  |  |  |
Unrecognized share-based compensation weighted average period | 2 months 12 days |  |  |  |  |
Restricted Stock Units [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Unrecognized share-based compensation cost | $ 23,501 |  |  |  |  |
Unrecognized share-based compensation weighted average period | 2 years 10 months 24 days |  |  |  |  |

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