Note 10 - Commitments and Contingencies (Details) - Anticipated Payments and Insurance Proceeds of Identified Environmental Remediation Liabilities (USD $) In Thousands, unless otherwise specified	Aug. 30, 2014	Aug. 31, 2013	Aug. 25, 2012
Anticipated Payments and Insurance Proceeds of Identified Environmental Remediation Liabilities [Abstract]
Estimated costs – current dollars	$ 5,219
Estimated costs – current dollars	1,915
Estimated costs – current dollars	1,663
Estimated costs – current dollars	745
Estimated costs – current dollars	863
Estimated costs – current dollars	12,407
Estimated costs – current dollars	22,812
Estimated insurance proceeds	(173)
Estimated insurance proceeds	(159)
Estimated insurance proceeds	(173)
Estimated insurance proceeds	(159)
Estimated insurance proceeds	(173)
Estimated insurance proceeds	(1,430)
Estimated insurance proceeds	(2,267)
Net anticipated costs	5,046
Net anticipated costs	1,756
Net anticipated costs	1,490
Net anticipated costs	586
Net anticipated costs	690
Net anticipated costs	10,977
Net anticipated costs	20,545
Effect of inflation	7,075
Effect of discounting	(7,774)
Balance as of August 30, 2014	$ 19,846	$ 19,680	$ 20,020