Note 8 - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for loan losses, beginning of period	$ 11,184	$ 10,826
Provision for (credit to) loan losses	0	275
Charge-offs	(31)	(32)
Recoveries	78	46
Allowance for loan losses, end of period	11,231	11,115
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for loan losses, beginning of period	3,368	4,050
Provision for (credit to) loan losses	(242)	(147)
Charge-offs	0	0
Recoveries	66	13
Allowance for loan losses, end of period	3,192	3,916
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for loan losses, beginning of period	363	346
Provision for (credit to) loan losses	346	(33)
Charge-offs	0	0
Recoveries	0	0
Allowance for loan losses, end of period	709	313
Commercial Portfolio Segment [Member] \| Secured by Commercial Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for loan losses, beginning of period	4,280	3,736
Provision for (credit to) loan losses	(467)	358
Charge-offs	0	0
Recoveries	0	0
Allowance for loan losses, end of period	3,813	4,094
Commercial Portfolio Segment [Member] \| Secured by Residential Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for loan losses, beginning of period	1,035	871
Provision for (credit to) loan losses	(9)	(57)
Charge-offs	0	0
Recoveries	3	11
Allowance for loan losses, end of period	1,029	825
State and Political Subdivisions Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for loan losses, beginning of period	69	89
Provision for (credit to) loan losses	(1)	(3)
Charge-offs	0	0
Recoveries	0	0
Allowance for loan losses, end of period	68	86
Retail Portfolio Segment [Member] \| Consumer Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for loan losses, beginning of period	542	265
Provision for (credit to) loan losses	69	10
Charge-offs	(31)	(32)
Recoveries	8	20
Allowance for loan losses, end of period	588	263
Retail Portfolio Segment [Member] \| Family Residential Mortgages [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for loan losses, beginning of period	646	533
Provision for (credit to) loan losses	19	77
Charge-offs	0	0
Recoveries	0	0
Allowance for loan losses, end of period	665	610
Retail Portfolio Segment [Member] \| Home Equity Loans and Lines [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for loan losses, beginning of period	376	386
Provision for (credit to) loan losses	21	(20)
Charge-offs	0	0
Recoveries	1	2
Allowance for loan losses, end of period	398	368
Unallocated Financing Receivables [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for loan losses, beginning of period	505	550
Provision for (credit to) loan losses	264	90
Charge-offs	0	0
Recoveries	0	0
Allowance for loan losses, end of period	$ 769	$ 640

Provision for (credit to) loan and lease losses.

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=122038336&loc=d3e74567-122707

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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