Note 2 - Investments - Schedule of Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023
Debt Securities, Available-for-sale, Adjusted Cost	$ 27,370	$ 29,372
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(1,507)	(1,453)
Debt Securities, Available-for-sale, Fair Value	25,863	27,919
Total	25,863	27,919
Bank Time Deposits [Member]
Maturities from 1-90 days, time deposit	0	0
Corporate & Government Debt Mutual Funds Securities [Member]
Debt Securities, Available-for-sale, Adjusted Cost	19,995	19,990
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(1,074)	(1,025)
Debt Securities, Available-for-sale, Fair Value	18,921	18,965
financial instrument, short-term investments	18,921	18,965
Corporate & Government Debt ETFs Securities [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	(433)	(418)
Debt Securities, Available-for-sale, Fair Value	6,942	6,958
financial instrument, short-term investments	6,942	6,958
Interest-bearing Time Deposits [Member]
Debt Securities, Available-for-sale, Adjusted Cost	0	2,006
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	0	(10)
Debt Securities, Available-for-sale, Fair Value	0	1,996
financial instrument, short-term investments	$ 0	$ 1,996

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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