Note 2 - Investments - Schedule of Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022
Debt Securities, Available-for-sale, Adjusted Cost	$ 32,242	$ 27,372
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(1,567)	(1,199)
Debt Securities, Available-for-sale, Fair Value	30,675	26,173
financial instrument, short-term investments	30,675	26,173
Corporate & Government Debt Mutual Funds Securities [Member]
Debt Securities, Available-for-sale, Adjusted Cost	19,997	19,997
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(1,042)	(806)
Debt Securities, Available-for-sale, Fair Value	18,955	19,191
financial instrument, short-term investments	18,955	19,191
Corporate & Government Debt ETFs Securities [Member]
Debt Securities, Available-for-sale, Adjusted Cost	7,375	7,375
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(498)	(393)
Debt Securities, Available-for-sale, Fair Value	6,877	6,982
financial instrument, short-term investments	6,877	6,982
Interest-bearing Time Deposits [Member]
Debt Securities, Available-for-sale, Adjusted Cost	4,870	0
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(27)	0
Debt Securities, Available-for-sale, Fair Value	4,843	0
Interest-bearing Time Deposits [Member] \| Cash and Cash Equivalents [Member]
financial instrument, short-term investments	0	0
Interest-bearing Time Deposits [Member] \| Short-Term Investments [Member]
financial instrument, short-term investments	$ 4,843	$ 0

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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