Note 6 - Pledged Assets - Schedule of Financial Instruments Pledged as Collateral From Counterparties (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Cash	$ 12,572	$ 16,293
Repurchase Agreements [Member]
Cash	0	3,272
Derivative [Member]
Cash	12,572	13,021
Cash [Member]
Cash	12,572	16,096
Cash [Member] | Repurchase Agreements [Member]
Cash	0	3,075
Cash [Member] | Derivative [Member]
Cash	12,572	13,021
US Treasury Securities [Member]
Cash	0	197
US Treasury Securities [Member] | Repurchase Agreements [Member]
Cash	0	197
US Treasury Securities [Member] | Derivative [Member]
Cash	$ 0	$ 0