Note 2 - Investments - Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Mar. 31, 2023		Jun. 30, 2022
Statement [Line Items]
Amortized cost	$ 8,006	[1]	$ 8,576
Amortized Cost	1,000
Investments in debt securities	7,649	[1]	$ 10,625
Fair Value, held to maturity debt securities, due after five years through ten years	$ 755

[1] Principal payments of $750,000 are due quarterly with a final maturity date in January 2026.