Note 4 - Loans - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Balance	$ 166,538	$ 123,224	$ 122,391
Provision/(reversal) for loan losses	(11,210)	57,500	(7,000)
Charge-offs	(20,054)	(21,996)	(6,997)
Recoveries	2,443	7,810	14,830
Net (Charge-offs)/Recoveries	(17,611)	(14,186)
Balance	136,157	166,538	123,224
Reserve for impaired loans		6,429
Reserve for non-impaired loans		160,109
Reserve for off-balance sheet credit commitments		5,880
(Reversal)/provision for credit losses	(16,008)	57,500	(7,000)
Commitments to Extend Credit [Member]
Balance	5,880
Balance	7,100	5,880
(Reversal)/provision for credit losses	(4,798)
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Balance	(1,560)	0	0
Balance		(1,560)	0
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Commitments to Extend Credit [Member]
Balance	6,018
Balance		6,018
Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance	164,978
Balance		164,978
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Commitments to Extend Credit [Member]
Balance	11,898
Balance		11,898
Commercial Portfolio Segment [Member]
Balance	68,742	57,021
Provision/(reversal) for loan losses	24,463	26,450
Charge-offs	(20,051)	(21,996)
Recoveries	1,706	7,267
Net (Charge-offs)/Recoveries	(18,345)	(14,729)
Balance	43,394	68,742	57,021
Reserve for impaired loans		1,030
Reserve for non-impaired loans		67,712
Reserve for off-balance sheet credit commitments		4,802
Commercial Portfolio Segment [Member] \| Commitments to Extend Credit [Member]
Balance	4,802
Balance	3,725	4,802
(Reversal)/provision for credit losses	(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, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Commitments to Extend Credit [Member]
Balance	3,236
Balance		3,236
Commercial Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance	37,276
Balance		37,276
Commercial Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Commitments to Extend Credit [Member]
Balance	8,038
Balance		8,038
Real Estate Construction Portfolio Segment [Member]
Balance	30,854	19,474
Provision/(reversal) for loan losses	(321)	11,380
Charge-offs	0	0
Recoveries	76	0
Net (Charge-offs)/Recoveries	76	0
Balance	6,302	30,854	19,474
Reserve for impaired loans		0
Reserve for non-impaired loans		30,854
Reserve for off-balance sheet credit commitments		690
Real Estate Construction Portfolio Segment [Member] \| Commitments to Extend Credit [Member]
Balance	690
Balance	3,375	690
(Reversal)/provision for credit losses	(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, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Commitments to Extend Credit [Member]
Balance	3,135
Balance		3,135
Real Estate Construction Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance	6,547
Balance		6,547
Real Estate Construction Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Commitments to Extend Credit [Member]
Balance	3,825
Balance		3,825
Commercial Real Estate Portfolio Segment [Member]
Balance	49,205	33,602
Provision/(reversal) for loan losses	(23,401)	15,164
Charge-offs	0	0
Recoveries	284	439
Net (Charge-offs)/Recoveries	284	439
Balance	61,081	49,205	33,602
Reserve for impaired loans		5,254
Reserve for non-impaired loans		43,951
Reserve for off-balance sheet credit commitments		101
Commercial Real Estate Portfolio Segment [Member] \| Commitments to Extend Credit [Member]
Balance	101
Balance	0	101
(Reversal)/provision for credit losses	(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, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Commitments to Extend Credit [Member]
Balance	(66)
Balance		(66)
Commercial Real Estate Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance	84,198
Balance		84,198
Commercial Real Estate Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Commitments to Extend Credit [Member]
Balance	35
Balance		35
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Balance	17,737	13,108
Provision/(reversal) for loan losses	(11,943)	4,525
Charge-offs	(3)	0
Recoveries	377	104
Net (Charge-offs)/Recoveries	374	104
Balance	25,379	17,737	13,108
Reserve for impaired loans		145
Reserve for non-impaired loans		17,592
Reserve for off-balance sheet credit commitments		284
Residential Mortgage and Equity Lines Portfolio Segment [Member] \| Commitments to Extend Credit [Member]
Balance	284
Balance	0	284
(Reversal)/provision for credit losses	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, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Commitments to Extend Credit [Member]
Balance	(284)
Balance		(284)
Residential Mortgage and Equity Lines Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance	36,948
Balance		36,948
Residential Mortgage and Equity Lines Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Commitments to Extend Credit [Member]
Balance	0
Balance		0
Installment and Other Loans [Member ]
Balance	0	19
Provision/(reversal) for loan losses	(8)	(19)
Charge-offs	0	0
Recoveries	(0)	0
Net (Charge-offs)/Recoveries	0	0
Balance	1	0	$ 19
Reserve for impaired loans		0
Reserve for non-impaired loans		0
Reserve for off-balance sheet credit commitments		3
Installment and Other Loans [Member ] \| Commitments to Extend Credit [Member]
Balance	3
Balance	0	3
(Reversal)/provision for credit losses	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, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Commitments to Extend Credit [Member]
Balance	(3)
Balance		(3)
Installment and Other Loans [Member ] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance	9
Balance		9
Installment and Other Loans [Member ] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Commitments to Extend Credit [Member]
Balance	$ 0
Balance		$ 0

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

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