Note 7 - Other Assets - Investments (Details) - USD ($)	Jun. 30, 2020	Jun. 30, 2019
Investments, cost	$ 1,815,961	$ 3,758,591
Investments, gross unrealized gains	5,161
Investments, gross unrealized losses	(606)	(1,995)
Investments	1,820,516	3,756,596
Money Market Funds [Member]
Investments, cost	1,044,446	3,005,182
Investments, gross unrealized gains	5,161
Investments, gross unrealized losses
Investments	1,049,607	3,005,182
Other Short Term Investments [Member]
Investments, cost	770,094	749,988
Investments, gross unrealized gains
Investments, gross unrealized losses		(739)
Investments	770,094	749,249
Other Equities [Member]
Investments, cost	1,421	3,421
Investments, gross unrealized gains
Investments, gross unrealized losses	(606)	(1,256)
Investments	$ 815	$ 2,165

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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