Note 9 - Business Segment Reporting (Details Textual)	3 Months Ended		12 Months Ended
	Aug. 26, 2018	Aug. 27, 2017	May 27, 2018
Number of Operating Segments	3		3
Sales Revenue, Net [Member] | Customer Concentration Risk [Member]
Entity Wide Revenue Major Customer Number	5	5
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Natural Foods [Member]
Entity Wide Revenue Major Customer Number		2
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Top Five Customers [Member]
Concentration Risk, Percentage	48.00%	47.00%
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Costco [Member] | Natural Foods [Member]
Concentration Risk, Percentage	19.00%	18.00%
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Wal-mart [Member] | Natural Foods [Member]
Concentration Risk, Percentage	18.00%	18.00%