Income Taxes (Reconciliation Of Statutory Federal Income Tax Rate To Effective Tax Rate) (Details)	12 Months Ended
Aug. 29, 2020	Aug. 31, 2019	Sep. 01, 2018	Dec. 31, 2017
Income Taxes [Abstract]
U.S. Federal statutory rate	21.00%	21.00%	25.60%	35.00%
State income taxes, net of Federal benefit	3.70%	3.70%	3.40%
Revaluation of Net Deferred Tax Liabilities			(10.00%)
Other, net		(0.10%)	(0.10%)
Effective income tax rate	24.70%	24.60%	18.90%

Increase (decrease) to net deferred tax liabilities due to revaluation

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

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