Note 10 - Changes to Environmental Liabilities (Details) - USD ($)	9 Months Ended
	May 28, 2016	May 30, 2015
Beginning balance as of August 29, 2015	$ 23,307,000
Costs incurred for which reserves had been provided	(820,000)
Insurance proceeds	68,000
Accretion on environmental contingencies	502,000	$ 452,000
Change in discount rates	579,000
Balance as of May 28, 2016	$ 23,636,000