Note 4 - Loans and the Allowance for Credit Losses - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Beginning balance	$ 12,867	$ 10,717
Provision charged to operations - loans	900	2,575
Charge-offs	(680)	(1,802)
Recoveries	70	848
Ending balance	13,157	12,867
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance	$ 0	529
Ending balance		$ 0