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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Business And Summary Of Significant Accounting Policies (Narrative) (Details) $ / shares in Units, shares in Thousands	1 Months Ended				12 Months Ended
	Nov. 30, 2018 $ / shares shares	Oct. 31, 2018 $ / shares shares	Sep. 30, 2018 $ / shares shares	Aug. 31, 2018 $ / shares shares	Aug. 31, 2019 USD ($) store segment warehouse	Sep. 01, 2018 USD ($)	Sep. 02, 2017 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of branch offices \| store					99
Number of customer fulfillment centers \| warehouse					12
Cash equivalents					$ 0	$ 0
Amortization expense					11,746,000	10,513,000	$ 8,223,000
Impairment loss					0	0	0
Deferred principal catalog costs					$ 3,363,000	3,973,000
Period deferred principal catalog costs remain the most current source of sales					1 year
Advertising costs					$ 18,812,000	15,530,000	16,289,000
Shipping and handling costs					138,242,000	130,340,000	119,979,000
Purchases of treasury stock					84,611,000	82,369,000	$ 49,182,000
Unrecognized tax benefit that would affect effective tax rate					$ 11,698,000	9,407,000
Number of Operating Segments \| segment					1
Number of reportable segments \| segment					1
Class A Common Stock [Member]
Summary Of Significant Accounting Policies [Line Items]
Repurchases of common stock, Shares \| shares	123	2	113	45
Cost of repurchase, per share \| $ / shares	$ 81.22	$ 85.00	$ 84.29	$ 82.64
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Original manufacturers warranty period					30 days
Minimum [Member] \| Accounting Standards Update 2016-02 [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated effect of accounting change					$ 55,000,000
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Warranty period					1 year
Original manufacturers warranty period					90 days
Maximum [Member] \| Accounting Standards Update 2016-02 [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated effect of accounting change					$ 65,000,000
Net Sales [Member] \| Geographic Concentration Risk [Member]
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage					100.00%
Net Sales [Member] \| Geographic Concentration Risk [Member] \| U.K., Canada, and Mexico [Member]
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage					4.00%
Leasehold Improvements And Buildings [Member] \| Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment estimated useful life					3 years
Leasehold Improvements And Buildings [Member] \| Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment estimated useful life					40 years
Computer Systems, Equipment And Software [Member] \| Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment estimated useful life					3 years
Computer Systems, Equipment And Software [Member] \| Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment estimated useful life					10 years
Furniture, Fixtures And Equipment [Member] \| Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment estimated useful life					3 years
Furniture, Fixtures And Equipment [Member] \| Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment estimated useful life					20 years
Trademarks [Member]
Summary Of Significant Accounting Policies [Line Items]
Impairment of intangible assets					$ 107,000	129,000
Customer Relationships And Trademarks [Member]
Summary Of Significant Accounting Policies [Line Items]
Intangible assets acquired during period					6,200,000	$ 23,285,000
Contract Rights [Member]
Summary Of Significant Accounting Policies [Line Items]
Write off of fully amortized assets					$ 23,100,000