Note 2 - Investments - Schedule of Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Jun. 30, 2022
Debt Securities, Available-for-sale, Adjusted Cost	$ 31,102	$ 27,372
Debt Securities, Available-for-sale, Unrealized Gain	0	0
Debt Securities, Available-for-sale, Unrealized Loss	(1,388)	(1,199)
Debt Securities, Available-for-sale, Fair Value	29,714	26,173
financial instrument, short-term investments	29,714	26,173
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	(962)	(806)
Debt Securities, Available-for-sale, Fair Value	19,028	19,191
financial instrument, short-term investments	19,028	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	(398)	(393)
Debt Securities, Available-for-sale, Fair Value	6,977	6,982
financial instrument, short-term investments	6,977	6,982
Interest-bearing Time Deposits [Member]
Debt Securities, Available-for-sale, Adjusted Cost	3,737
Debt Securities, Available-for-sale, Unrealized Gain	0
Debt Securities, Available-for-sale, Unrealized Loss	(28)
Debt Securities, Available-for-sale, Fair Value	3,709
financial instrument, short-term investments	$ 3,709	$ 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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