Note 3 - Investments - Schedule of Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Jun. 30, 2023
Debt Securities, Available-for-sale, Adjusted Cost	$ 22,651	$ 29,372
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(1,177)	(1,453)
Debt Securities, Available-for-sale, Fair Value	21,474	27,919
Financial instrument, long-term investments	0	0
Total	21,474	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	15,276	19,990
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(850)	(1,025)
Debt Securities, Available-for-sale, Fair Value	14,426	18,965
Financial instrument, short-term investments	14,426	18,965
Financial instrument, long-term investments	0	0
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	(327)	(418)
Debt Securities, Available-for-sale, Fair Value	7,048	6,958
Financial instrument, short-term investments	7,048	6,958
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	$ 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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