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Credit adjusted risk-free interest rate assumption used in valuing an asset retirement obligation.

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Note 1 - Summary of Significant Accounting Policies (Details Textual)			12 Months Ended
	Apr. 21, 2016 shares	Oct. 27, 2014 shares	Aug. 27, 2016 USD ($) $ / shares shares	Aug. 29, 2015 USD ($) $ / shares shares	Aug. 30, 2014 USD ($) $ / shares shares	Aug. 29, 2009	Oct. 30, 2010 shares	Nov. 30, 1996 shares
Machinery and Equipment [Member]
Capitalized Computer Software, Gross \| $			$ 47,900,000
Customer Contracts [Member]
Finite-Lived Intangible Asset, Useful Life			14 years 292 days
Other Intangible Assets [Member]
Finite-Lived Intangible Asset, Useful Life			5 years 109 days
Minimum [Member]
Credit Adjusted Risk Free Rate			7.00%
Maximum [Member]
Credit Adjusted Risk Free Rate			7.50%
Conversion of Class B Common Stock in to Common Stock [Member]
Common Stock Conversion Ratio			1
The 1996 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized								1,500,000
The 2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized							600,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized		750,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			787,010
Non-employee Director Share-based Award Grants Prior to Fiscal 2009 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			8 years			10 years
Certain Share-based Awards Granted During Fiscal 2014, 2013 and 2012 to Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			8 years
Restricted Shares Vesting for Threshold Performance [Member] \| Chief Executive Officer [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	100,000
Restricted Shares Vesting for Target Performance [Member] \| Chief Executive Officer [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	120,000
Restricted Shares Vesting for Exceeding Target Performance [Member] \| Chief Executive Officer [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	140,000
Chief Executive Officer [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	140,000
Impairment of Long-Lived Assets Held-for-use \| $			$ 0	$ 0	$ 0
Number of Reportable Segments			5
Rental Merchandise Useful Life, Minimum			180 days
Rental Merchandise Useful Life, Maximum			3 years
Goodwill and Intangible Asset Impairment \| $			$ 0	0	0
Finite-Lived Intangible Asset, Useful Life			14 years 36 days
Site Contingency Discount Rate, Lower Range			1.60%
Site Contingency Discount Rate, Upper Range			2.30%
Site Contingency Discounted Period, Lower Range			10 years
Site Contingency Discounted Period, Upper Range			30 years
Environmental Contingencies Inflation Rate			3.00%
Range of Years Discount for Estimated Future Costs to Decommission Its Nuclear Laundry Facilities, MinimumYears			1 year
Range of Years Discount for Estimated Future Costs to Decommission Its Nuclear Laundry Facilities, MaximumYears			28 years
Undistributed Earnings of Foreign Subsidiaries \| $			$ 124,800,000
Advertising Expense \| $			$ 1,500,000	$ 1,300,000	$ 1,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			5 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares			$ 35.81	$ 40.06	$ 39.08
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			9,883	10,702	185