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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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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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