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Associate Benefit Plans (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 1 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jul. 31, 2018 | Sep. 01, 2018 | Sep. 02, 2017 | Sep. 03, 2016 | 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 |  | 3,404 |  |  |  |  |
Shares purchased by qualified associates | 45 |  |  |  |  |  |
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 |  | 126 |  |  |  |  |
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 |  | 57 |  |  |  |  |
Share price |  | $ 78.65 | $ 74.81 |  |  |  |
Savings Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Company contributions to savings plan |  | $ 7,730 | $ 7,048 | $ 6,594 |  |  |
Stock Options [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Unrecognized share-based compensation cost |  | $ 7,529 |  |  |  |  |
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 |  | $ 7,516 | 9,474 | 3,129 |  |  |
Restricted Share Awards [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Fair value of shares vested |  | 7,222 | $ 7,357 | $ 7,518 |  |  |
Unrecognized share-based compensation cost |  | $ 1,920 |  |  |  |  |
Unrecognized share-based compensation weighted average period |  | 10 months 24 days |  |  |  |  |
Restricted Stock Units [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Unrecognized share-based compensation cost |  | $ 21,158 |  |  |  |  |
Unrecognized share-based compensation weighted average period |  | 3 years 2 months 12 days |  |  |  |  |

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- Definition Unrecognized cost of unvested share-based compensation awards. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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