Note 5 - Loans - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Balance	$ 136,157	$ 166,538
Provision/(reversal) for loan losses	12,913	(11,210)
Charge-offs	(5,490)	(20,054)
Recoveries	2,905	2,443
Net (Charge-offs)/Recoveries	(2,585)	(17,611)
Balance	146,485	136,157	$ 166,538
Provision/(reversal) for credit losses	14,543	(16,008)	57,500
Commitments to Extend Credit [Member]
Balance	7,100	11,898
Balance	8,730	7,100	11,898
Provision/(reversal) for credit losses	1,630	(4,798)
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		(1,560)
Balance			(1,560)
Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance		164,978
Balance			164,978
Commercial Portfolio Segment [Member]
Balance	43,394	68,742
Provision/(reversal) for loan losses	6,798	24,463
Charge-offs	(3,222)	(20,051)
Recoveries	2,465	1,706
Net (Charge-offs)/Recoveries	(757)	(18,345)
Balance	49,435	43,394	68,742
Commercial Portfolio Segment [Member] \| Commitments to Extend Credit [Member]
Balance	3,725	8,038
Balance	4,840	3,725	8,038
Provision/(reversal) for credit losses	1,115	(4,313)
Commercial Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		(31,466)
Balance			(31,466)
Commercial Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance		37,276
Balance			37,276
Real Estate Construction Portfolio Segment [Member]
Balance	6,302	30,854
Provision/(reversal) for loan losses	4,109	(321)
Charge-offs	0	0
Recoveries	6	76
Net (Charge-offs)/Recoveries	6	76
Balance	10,417	6,302	30,854
Real Estate Construction Portfolio Segment [Member] \| Commitments to Extend Credit [Member]
Balance	3,375	3,825
Balance	3,890	3,375	3,825
Provision/(reversal) for credit losses	515	(450)
Real Estate Construction Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		(24,307)
Balance			(24,307)
Real Estate Construction Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance		6,547
Balance			6,547
Commercial Real Estate Portfolio Segment [Member]
Balance	61,081	49,205
Provision/(reversal) for loan losses	9,018	(23,401)
Charge-offs	(2,091)	0
Recoveries	358	284
Net (Charge-offs)/Recoveries	(1,733)	284
Balance	68,366	61,081	49,205
Commercial Real Estate Portfolio Segment [Member] \| Commitments to Extend Credit [Member]
Balance	0	35
Balance	0	0	35
Provision/(reversal) for credit losses	0	(35)
Commercial Real Estate Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		34,993
Balance			34,993
Commercial Real Estate Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance		84,198
Balance			84,198
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Balance	25,379	17,737
Provision/(reversal) for loan losses	(7,219)	(11,943)
Charge-offs	0	(3)
Recoveries	72	377
Net (Charge-offs)/Recoveries	72	374
Balance	18,232	25,379	17,737
Residential Mortgage and Equity Lines Portfolio Segment [Member] \| Commitments to Extend Credit [Member]
Balance	0	0
Balance	0	0	0
Provision/(reversal) for credit losses	0	0
Residential Mortgage and Equity Lines Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		19,211
Balance			19,211
Residential Mortgage and Equity Lines Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance		36,948
Balance			36,948
Installment and Other Loans [Member ]
Balance	1	0
Provision/(reversal) for loan losses	207	(8)
Charge-offs	(177)	0
Recoveries	4	(0)
Net (Charge-offs)/Recoveries	(173)	0
Balance	35	1	0
Installment and Other Loans [Member ] \| Commitments to Extend Credit [Member]
Balance	0	0
Balance	0	0	0
Provision/(reversal) for credit losses	$ 0	0
Installment and Other Loans [Member ] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance		9
Balance			9
Installment and Other Loans [Member ] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance		$ 9
Balance			$ 9

Financing Receivable, Allowance For Credit Losses, Net Charge-Offs

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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