Note 3 - Investments, Held to Maturity - Summary of Held to Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Amortized cost, HTM	$ 163,072	$ 167,438
Gross unrealized gains, HTM	867	279
Gross unrealized losses, HTM	(5,399)	(6,253)
HTM, fair value	158,540	161,464
US Treasury and Government [Member]
Amortized cost, HTM	23,874	34,512
Gross unrealized gains, HTM	0	0
Gross unrealized losses, HTM	(278)	(682)
HTM, fair value	23,596	33,830
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member]
Amortized cost, HTM	1,000	1,000
Gross unrealized gains, HTM	0	0
Gross unrealized losses, HTM	0	(1)
HTM, fair value	1,000	999
Collateralized Loan Obligations [Member]
Amortized cost, HTM	16,881	16,388
Gross unrealized gains, HTM	278	88
Gross unrealized losses, HTM	0	(59)
HTM, fair value	17,159	16,417
Small Business Administration Bonds [Member]
Amortized cost, HTM	11,305	3,521
Gross unrealized gains, HTM	493	162
Gross unrealized losses, HTM	0	0
HTM, fair value	11,798	3,683
Taxable Municipal Bonds [Member]
Amortized cost, HTM	962	952
Gross unrealized gains, HTM	0	0
Gross unrealized losses, HTM	(28)	(60)
HTM, fair value	934	892
Collateralized Mortgage-Backed Securities [Member]
Amortized cost, HTM	109,050	111,065
Gross unrealized gains, HTM	96	29
Gross unrealized losses, HTM	(5,093)	(5,451)
HTM, fair value	$ 104,053	$ 105,643