Note 4 - Loans, Allowance for Loan Losses/Credit Losses and Other Real Estate Owned - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Balance at beginning of period, prior to adoption of ASU 2016-13	$ 19,484	$ 21,351
Provision (reversal)	4,300	0
Chargeoffs	(1,573)	(1,391)
Recoveries	576	517
Total allowance for credit losses (loans)	24,804	20,477
Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	2,017
Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	21,501
Unallocated Financing Receivable [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	3,701	3,177
Provision (reversal)	0	272
Chargeoffs	0	0
Recoveries	0	0
Total allowance for credit losses (loans)	0	3,449
Unallocated Financing Receivable [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	(3,701)
Unallocated Financing Receivable [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	0
Commercial Portfolio Segment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	4,959	6,311
Provision (reversal)	27	125
Chargeoffs	(178)	(23)
Recoveries	143	93
Total allowance for credit losses (loans)	8,336	6,506
Commercial Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	3,385
Commercial Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	8,344
Commercial Real Estate Portfolio Segment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	4,064	3,884
Provision (reversal)	59	31
Chargeoffs	0	0
Recoveries	12	12
Total allowance for credit losses (loans)	4,753	3,927
Commercial Real Estate Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	618
Commercial Real Estate Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	4,682
Construction Portfolio Segment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	109	1,465
Provision (reversal)	29	(612)
Chargeoffs	0	0
Recoveries	0	0
Total allowance for credit losses (loans)	107	853
Construction Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	(31)
Construction Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	78
Residential Portfolio Segment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	206	869
Provision (reversal)	(4)	(608)
Chargeoffs	0	0
Recoveries	0	0
Total allowance for credit losses (loans)	70	261
Residential Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	(132)
Residential Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	74
Consumer Portfolio Segment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	6,445	5,645
Provision (reversal)	4,189	792
Chargeoffs	(1,395)	(1,368)
Recoveries	421	412
Total allowance for credit losses (loans)	11,538	$ 5,481
Consumer Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	1,878
Consumer Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Balance at beginning of period, prior to adoption of ASU 2016-13	$ 8,323

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 credit loss expense (reversal of expense) for financing receivable.

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