Note 7 - Income Taxes (Details Textual) - USD ($)	12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2013
Domestic Tax Authority [Member] | Latest Tax Year [Member]
Open Tax Year	2012
State and Local Jurisdiction [Member] | Earliest Tax Year [Member]
Open Tax Year	2011
Deferred Tax Assets, Operating Loss Carryforwards, Domestic	$ 29,500,000	$ 27,500,000	$ 23,600,000
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	20,600,000	20,900,000	16,300,000
Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount	2,700,000	$ 1,900,000	$ 2,000,000
Unrecognized Tax Benefits, Period Increase (Decrease)	$ (532,000)