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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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