Note 7 - Income Taxes (Details Textual) - USD ($)	3 Months Ended	12 Months Ended
	Feb. 28, 2016	May 29, 2016	May 31, 2015	May 25, 2014	May 26, 2013
GreenLine Trademark [Member]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	$ 34,000,000	$ 34,000,000
Domestic Tax Authority [Member] | California [Member]
Operating Loss Carryforwards		$ 413,000
Domestic Tax Authority [Member] | Earliest Tax Year [Member]
Open Tax Year		1997
Domestic Tax Authority [Member]
Operating Loss Carryforwards		$ 7,300,000
State and Local Jurisdiction [Member] | Indiana [Member]
Operating Loss Carryforwards		6,500,000
State and Local Jurisdiction [Member] | Other States, Tax Board [Member]
Operating Loss Carryforwards		13,000,000
State and Local Jurisdiction [Member] | California Franchise Tax Board [Member]
Deferred Tax Asset, Operating Loss, Recorded to Additional Paid in Capital		413,000
Deferred Tax Assets, Tax Credit Carryforwards, Research		1,300,000
Deferred Tax Asset, Research and Development Credit, Recorded to Additional Paid in Capital		$ 1,100,000
State and Local Jurisdiction [Member] | Earliest Tax Year [Member]
Open Tax Year		1998
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		35.00%	35.00%	35.00%
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)		$ 34,000,000
Effective Income Tax Rate Reconciliation, Percent		39.00%	36.00%
Decrease in Net Income Before Taxes			28.00%
Deferred Tax Assets, Valuation Allowance		$ 1,240,000	$ 1,234,000
Unrecognized Tax Benefits		842,000	987,000	$ 1,035,000	$ 998,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate		715,000	$ 800,000
Decrease in Unrecognized Tax Benefits is Reasonably Possible		$ 300,000