Note 7 - Investments, Held to Maturity ("HTM") - Summary of HTM Securities in Unrealized Loss Position (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair value, less than 12 months, HTM	$ 4,021	$ 40,732
Unrealized losses, less then 12 months, HTM	(46)	(458)
Fair value, more than 12 months, HTM	81,093	83,261
Unrealized loss, more than 12 months, HTM	(5,256)	(4,941)
Fair value, unrealized loss position, HTM	85,114	123,993
Unrealized loss, unrealized loss position, HTM	(5,302)	(5,399)
US Treasury and Government [Member]
Fair value, less than 12 months, HTM	0	0
Unrealized losses, less then 12 months, HTM	0	0
Fair value, more than 12 months, HTM	23,655	23,596
Unrealized loss, more than 12 months, HTM	(249)	(278)
Fair value, unrealized loss position, HTM	23,655	23,596
Unrealized loss, unrealized loss position, HTM	(249)	(278)
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member]
Fair value, less than 12 months, HTM	998
Unrealized losses, less then 12 months, HTM	(2)
Fair value, more than 12 months, HTM	0
Unrealized loss, more than 12 months, HTM	0
Fair value, unrealized loss position, HTM	998
Unrealized loss, unrealized loss position, HTM	(2)
Taxable Municipal Bonds [Member]
Fair value, less than 12 months, HTM	0	0
Unrealized losses, less then 12 months, HTM	0	0
Fair value, more than 12 months, HTM	933	934
Unrealized loss, more than 12 months, HTM	(32)	(28)
Fair value, unrealized loss position, HTM	933	934
Unrealized loss, unrealized loss position, HTM	(32)	(28)
Collateralized Mortgage-Backed Securities [Member]
Fair value, less than 12 months, HTM	3,023	40,732
Unrealized losses, less then 12 months, HTM	(44)	(458)
Fair value, more than 12 months, HTM	56,505	58,731
Unrealized loss, more than 12 months, HTM	(4,975)	(4,635)
Fair value, unrealized loss position, HTM	59,528	99,463
Unrealized loss, unrealized loss position, HTM	$ (5,019)	$ (5,093)