Note 3 - Investments - Schedule of Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Jun. 30, 2022
Debt Securities, Available-for-sale, Adjusted Cost	$ 29,372	$ 27,372
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(1,453)	(1,199)
Debt Securities, Available-for-sale, Fair Value	27,919	26,173
financial instrument, long-term investments	0	0
Total	27,919	26,173
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	19,990	19,997
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(1,025)	(806)
Debt Securities, Available-for-sale, Fair Value	18,965	19,191
financial instrument, short-term investments	18,965	19,191
financial instrument, long-term investments	0	0
Corporate & Government Debt ETFs Securities [Member]
Debt Securities, Available-for-sale, Adjusted Cost	7,376	7,375
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(418)	(393)
Debt Securities, Available-for-sale, Fair Value	6,958	6,982
financial instrument, short-term investments	6,958	6,982
financial instrument, long-term investments	0	0
Interest-bearing Time Deposits [Member]
Debt Securities, Available-for-sale, Adjusted Cost	2,006
Debt Securities, Available-for-sale, Unrealized Gain	0
Debt Securities, Available-for-sale, Unrealized Loss	(10)
Debt Securities, Available-for-sale, Fair Value	1,996
financial instrument, short-term investments	$ 1,996	$ 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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