Note 8 - Loans - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Balance	$ 154,562	$ 146,485	$ 146,485
(Reversal)/provision for expected credit losses	1,167	3,255
Charge-offs	(2,193)	(7,907)	(23,486)
Recoveries	1,053	3,051
Net (charge-offs)/recoveries	(1,140)	(4,856)
Balance	154,589	144,884	154,562
Commitments to Extend Credit [Member]
Balance	9,053	8,730	8,730
(Reversal)/provision for expected credit losses	733	4,845
Balance	9,786	13,575	9,053
Commercial Portfolio Segment [Member]
Balance	53,791	49,435	49,435
(Reversal)/provision for expected credit losses	(1,374)	(60)
Charge-offs	(1,939)	(3,911)	(13,909)
Recoveries	812	511
Net (charge-offs)/recoveries	(1,127)	(3,400)
Balance	51,290	45,975	53,791
Commercial Portfolio Segment [Member] | Commitments to Extend Credit [Member]
Balance	6,888	4,840	4,840
(Reversal)/provision for expected credit losses	572	3,435
Balance	7,460	8,275	6,888
Real Estate Construction Portfolio Segment [Member]
Balance	8,180	10,417	10,417
(Reversal)/provision for expected credit losses	359	483
Charge-offs	0	0	(4,221)
Recoveries	0	0
Net (charge-offs)/recoveries	0	0
Balance	8,539	10,900	8,180
Real Estate Construction Portfolio Segment [Member] | Commitments to Extend Credit [Member]
Balance	2,165	3,890	3,890
(Reversal)/provision for expected credit losses	161	1,325
Balance	2,326	5,215	2,165
Commercial Real Estate Portfolio Segment [Member]
Balance	74,428	68,366	68,366
(Reversal)/provision for expected credit losses	2,872	3,463
Charge-offs	(251)	(3,990)	(5,341)
Recoveries	0	2,528
Net (charge-offs)/recoveries	(251)	(1,462)
Balance	77,049	70,367	74,428
Commercial Real Estate Portfolio Segment [Member] | Commitments to Extend Credit [Member]
Balance	0	0	0
(Reversal)/provision for expected credit losses	0	85
Balance	0	85	0
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Balance	18,140	18,232	18,232
(Reversal)/provision for expected credit losses	(677)	(611)
Charge-offs	(3)	0
Recoveries	241	12
Net (charge-offs)/recoveries	238	12
Balance	17,701	17,633	18,140
Residential Mortgage and Equity Lines Portfolio Segment [Member] | Commitments to Extend Credit [Member]
Balance	0	0	0
(Reversal)/provision for expected credit losses	0	0
Balance	0	0	0
Installment and Other Loans [Member ]
Balance	23	35	35
(Reversal)/provision for expected credit losses	(13)	(20)
Charge-offs	0	(6)	(15)
Recoveries	0	0
Net (charge-offs)/recoveries	0	(6)
Balance	10	9	23
Installment and Other Loans [Member ] | Commitments to Extend Credit [Member]
Balance	0	0	0
(Reversal)/provision for expected credit losses	0	0
Balance	$ 0	$ 0	$ 0