Note 5 - Loans Payable and Long-term Debt (Details Textual) - USD ($)	12 Months Ended
	Aug. 27, 2016		Aug. 29, 2015
Revolving Credit Facility [Member] | Credit Agreement [Member]
Debt Instrument, Maturity Date	Apr. 11, 2021
Long-term Line of Credit	$ 0
Line of Credit Facility, Maximum Borrowing Capacity	250,000,000
Letters of Credit Outstanding, Amount	53,000,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 197,000,000
Credit Agreement [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	0.75%
Loans Payable, Current	$ 0	[1]	$ 1,385,000
Letters of Credit Outstanding, Amount	$ 53,000,000		$ 52,900,000

[1] In the second fiscal quarter of 2016, the Company adopted updated accounting guidance on the presentation of deferred income taxes. This adoption required that deferred tax liabilities and assets be classified as noncurrent in the Consolidated Balance Sheet. The Company elected to account for this change in presentation prospectively and prior periods were not retroactively adjusted.