Note 2 - Investments - Schedule of Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Jun. 30, 2021
Debt Securities, Available-for-sale, Adjusted Cost	$ 27,372	$ 27,374
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(792)	(23)
Debt Securities, Available-for-sale, Fair Value	26,580	27,351
Corporate & Government Debt Securities [Member] \| Mutual Fund [Member]
Debt Securities, Available-for-sale, Adjusted Cost	19,997	19,998
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(510)	(13)
Debt Securities, Available-for-sale, Fair Value	19,487	19,985
Corporate & Government Debt Securities [Member] \| Exchange Traded Funds [Member]
Debt Securities, Available-for-sale, Adjusted Cost	7,375	7,376
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(282)	(10)
Debt Securities, Available-for-sale, Fair Value	$ 7,093	$ 7,366

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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