Note 3 - Investments - Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Sep. 30, 2023		Jun. 30, 2023
Investments in available-for-sale debt securities, amortized cost	$ 7,414	[1]	$ 7,729
Amortized Cost	1,000
Investments in debt securities	6,343	[1]	$ 7,008
Fair Value, held to maturity debt securities, due after five years through ten years	$ 795

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