Note 5 - Components of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Accumulated Other Comprehensive Loss [Line Items]
Accumulated other loss	$ (84,268)	$ (85,996)
Tax effect	17,697	18,059
Accumulated other comprehensive loss, net of tax	(66,571)	(67,937)
Unrealized Net Holding Losses on Available-for-sale Securities [Member]
Accumulated Other Comprehensive Loss [Line Items]
Accumulated other loss	(88,713)	(84,247)
Unrealized Net Holding Gains (Losses) on Fair Value Hedge [Member]
Accumulated Other Comprehensive Loss [Line Items]
Accumulated other loss	$ 4,445	$ (1,749)