Note 9 - Loans - Activity in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Balance		$ 145,786	$ 145,110	$ 136,157	$ 166,538	$ 166,538
Provision/(reversal) for possible credit losses		2,768	(6,600)	12,107	(18,710)
Charge-offs		(51)	(7,712)	(272)	(16,850)
Recoveries		269	458	780	1,838
Net (charge-offs)/recoveries		218	(7,254)	508	(15,012)	(17,611)
Balance		148,772	131,256	148,772	131,256	136,157
Charge-offs		(51)	(7,712)	(272)	(16,850)
Recoveries		269	458	780	1,838
Commitments to Extend Credit [Member]
Balance		6,404	10,450	7,100	5,880	5,880
Provision/(reversal) for possible credit losses		(268)	(2,400)	(964)	(3,848)
Balance		6,136	8,050	6,136	8,050	7,100
Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member]
Balance					(1,560)	(1,560)
Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member] | Commitments to Extend Credit [Member]
Balance	[1]				6,018	6,018
Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance					164,978	164,978
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Commitments to Extend Credit [Member]
Balance					11,898	11,898
Commercial Portfolio Segment [Member]
Balance		44,738	42,034	43,394	68,742	68,742
Provision/(reversal) for possible credit losses		4,208	5,590	5,414	18,216
Charge-offs		(50)	(7,712)	(271)	(16,850)	(20,051)
Recoveries		175	155	534	1,425	1,706
Net (charge-offs)/recoveries		125	(7,557)	263	(15,425)	(18,345)
Balance		49,071	40,067	49,071	40,067	43,394
Charge-offs		(50)	(7,712)	(271)	(16,850)	(20,051)
Recoveries		175	155	534	1,425	1,706
Commercial Portfolio Segment [Member] | Commitments to Extend Credit [Member]
Balance		3,177	8,163	3,725	4,802	4,802
Provision/(reversal) for possible credit losses		(373)	(3,775)	(921)	(3,650)
Balance		2,804	4,388	2,804	4,388	3,725
Commercial Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member]
Balance					(31,466)	(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	[1]				3,236	3,236
Commercial Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance					37,276	37,276
Commercial Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Commitments to Extend Credit [Member]
Balance					8,038	8,038
Real Estate Construction Portfolio Segment [Member]
Balance		7,436	6,992	6,302	30,854	30,854
Provision/(reversal) for possible credit losses		(160)	(873)	968	(428)
Charge-offs		0	0	0	0	0
Recoveries		0	0	6	0	76
Net (charge-offs)/recoveries		0	0	6	0	76
Balance		7,276	6,119	7,276	6,119	6,302
Charge-offs		0	0	0	0	0
Recoveries		0	0	6	0	76
Real Estate Construction Portfolio Segment [Member] | Commitments to Extend Credit [Member]
Balance		3,227	2,251	3,375	690	690
Provision/(reversal) for possible credit losses		79	1,330	(69)	(244)
Balance		3,306	3,581	3,306	3,581	3,375
Real Estate Construction Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member]
Balance					(24,307)	(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	[1]				3,135	3,135
Real Estate Construction Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance					6,547	6,547
Real Estate Construction Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Commitments to Extend Credit [Member]
Balance					3,825	3,825
Commercial Real Estate Portfolio Segment [Member]
Balance		63,878	65,347	61,081	49,205	49,205
Provision/(reversal) for possible credit losses		4,634	(7,416)	7,336	(26,362)
Charge-offs		0	0	0	0	0
Recoveries		88	95	183	190	379
Net (charge-offs)/recoveries		88	95	183	190	379
Balance		68,600	58,026	68,600	58,026	61,081
Charge-offs		0	0	0	0	0
Recoveries		88	95	183	190	379
Commercial Real Estate Portfolio Segment [Member] | Commitments to Extend Credit [Member]
Balance		0	36	0	101	101
Provision/(reversal) for possible credit losses		26	45	26	46
Balance		26	81	26	81	0
Commercial Real Estate Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member]
Balance					34,993	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	[1]				(66)	(66)
Commercial Real Estate Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance					84,198	84,198
Commercial Real Estate Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Commitments to Extend Credit [Member]
Balance					35	35
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Balance		29,630	30,734	25,379	17,737	17,737
Provision/(reversal) for possible credit losses		(5,945)	(3,899)	(1,745)	(10,128)
Charge-offs		0	0	0	0
Recoveries		6	208	57	223
Net (charge-offs)/recoveries		6	208	57	223
Balance		23,691	27,043	23,691	27,043	25,379
Charge-offs		0	0	0	0
Recoveries		6	208	57	223
Residential Mortgage and Equity Lines Portfolio Segment [Member] | Commitments to Extend Credit [Member]
Balance		0	0	0	284	284
Provision/(reversal) for possible credit losses		0	0	0	0
Balance		0	0	0	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	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	[1]				(284)	(284)
Residential Mortgage and Equity Lines Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance					36,948	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	0
Installment and Other Loans [Member ]
Balance		104	3	1	0	0
Provision/(reversal) for possible credit losses		31	(2)	134	(8)
Charge-offs		(1)	0	(1)	0	0
Recoveries		0	0	(0)	0	(0)
Net (charge-offs)/recoveries		(1)	0	(1)	0	0
Balance		134	1	134	1	1
Charge-offs		(1)	0	(1)	0	0
Recoveries		0	0	(0)	0	(0)
Installment and Other Loans [Member ] | Commitments to Extend Credit [Member]
Balance		0	0	0	3	3
Provision/(reversal) for possible credit losses		0	0	0	0
Balance		$ 0	$ 0	$ 0	0	0
Installment and Other Loans [Member ] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Accounting Standards Update 2016-13 [Member]
Balance					9	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	[1]				(3)	(3)
Installment and Other Loans [Member ] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance					9	9
Installment and Other Loans [Member ] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Commitments to Extend Credit [Member]
Balance					$ 0	$ 0

[1] Balance sheet amounts previously reported for the impact of the initial adoption of CECL on January 1, 2021 have been corrected. The correction decreased the allowance for loan losses by $2.2 million and increased the allowance for unfunded credit commitments by $5.5 million.