Note 2 - Acquisitions (Details) (USD $)	0 Months Ended	6 Months Ended					6 Months Ended	0 Months Ended	6 Months Ended
	Aug. 23, 2012	Nov. 24, 2013	Nov. 25, 2012	May 26, 2013		Apr. 23, 2012	Nov. 24, 2013 GreenLine [Member] Customer Base [Member]	Apr. 23, 2012 GreenLine [Member]	Nov. 24, 2013 GreenLine [Member]
Note 2 - Acquisitions (Details) [Line Items]
Number of Processing Plants								4
Business Combination, Consideration Transferred	$ 66,833,000							$ 66,800,000
Effective Income Tax Rate Reconciliation, Percent		34.00%	29.00%						40.00%
Number of Intangible Assets Identified									2
Indefinite Lived Intangible Assets Market Value									36,000,000
Finite-lived Intangible Assets Acquired							7,500,000
Finite-Lived Intangible Asset, Useful Life							13 years
Goodwill		$ 49,620,000		$ 49,620,000	[1]	$ 13,158,000			$ 13,200,000

[1] Derived from audited financial statements.