Note 3 - Investments, Held to Maturity - Summary of HTM Securities in Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair value, less than 12 months, HTM	$ 40,732	$ 130,592
Unrealized losses, less then 12 months, HTM	458	3,947
Fair value, more than 12 months, HTM	83,261	9,334
Unrealized loss, more than 12 months, HTM	4,941	2,306
Fair value, unrealized loss position, HTM	123,993	139,926
Unrealized loss, unrealized loss position, HTM	5,399	6,253
US Treasury and Government [Member]
Fair value, less than 12 months, HTM	0	33,830
Unrealized losses, less then 12 months, HTM	0	682
Fair value, more than 12 months, HTM	23,596	0
Unrealized loss, more than 12 months, HTM	278	0
Fair value, unrealized loss position, HTM	23,596	33,830
Unrealized loss, unrealized loss position, HTM	278	682
Taxable Municipal Bonds [Member]
Fair value, less than 12 months, HTM	0	892
Unrealized losses, less then 12 months, HTM	0	60
Fair value, more than 12 months, HTM	934	0
Unrealized loss, more than 12 months, HTM	28	0
Fair value, unrealized loss position, HTM	934	892
Unrealized loss, unrealized loss position, HTM	28	60
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member]
Fair value, less than 12 months, HTM		999
Unrealized losses, less then 12 months, HTM		1
Fair value, more than 12 months, HTM		0
Unrealized loss, more than 12 months, HTM		0
Fair value, unrealized loss position, HTM		999
Unrealized loss, unrealized loss position, HTM		1
Collateralized Mortgage-Backed Securities [Member]
Fair value, less than 12 months, HTM	40,732	88,351
Unrealized losses, less then 12 months, HTM	458	3,145
Fair value, more than 12 months, HTM	58,731	9,334
Unrealized loss, more than 12 months, HTM	4,635	2,306
Fair value, unrealized loss position, HTM	99,463	97,685
Unrealized loss, unrealized loss position, HTM	$ 5,093	5,451
Collateralized Loan Obligations [Member]
Fair value, less than 12 months, HTM		6,520
Unrealized losses, less then 12 months, HTM		59
Fair value, more than 12 months, HTM		0
Unrealized loss, more than 12 months, HTM		0
Fair value, unrealized loss position, HTM		6,520
Unrealized loss, unrealized loss position, HTM		$ 59