Note 3 - Investments - Unrealized Gains and Losses (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Net gains and losses recognized during the period		$ 358	$ (937)	$ (904)	$ (2,868)
Less: Net gains and losses recognized during the period on securities sold during the period		79	0	35	0
Net unrealized gains (losses) recognized during the reporting period on securities still held at the reporting date (1)	[1]	279	(937)	(939)	(2,868)
Net gains and losses recognized during the period		46	0	46	0
Less: Net gains and losses recognized during the period on securities sold during the period		0	0	0	0
Corporate debt securities		$ 46	$ 0	$ 46	$ 0

[1] Includes net unrealized and realized losses as a result of the measurement alternative of $0 and $775,000 for the three and six months ended December 31, 2023, net unrealized and realized gains of $5,000 for the three months ended December 31, 2022, and net unrealized and realized losses of $1.8 million, for the six months ended December 31, 2022.