Note 22 - Commitments and Credit Risk (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Letters of Credit Outstanding, Amount	$ 10,256,000	$ 5,446,000
Loans and Leases Receivable, Gross, Total	753,408,413	728,914,025
Assumable Rate Conversion Loan Agreement [Member]
Loans and Leases Receivable, Gross, Total	72,400,000
Brokerage Commissions Revenue	1,100,000
Guarantor Obligations, Current Carrying Value	0
Commercial Loans [Member] \| Unused lines of Credit [Member]
Other Commitment, Total	107,444,000	108,257,000
Open End Consumer Lines [Member] \| Unused lines of Credit [Member]
Other Commitment, Total	24,746,000	24,373,000
Confirming Letters of Credit From FHLB [Member]
Letters of Credit Outstanding, Amount	$ 62,239,000	57,771,000
Standby Letters of Credit [Member] \| Minimum [Member]
Debt Instrument, Term (Year)	1 year
Standby Letters of Credit [Member] \| Maximum [Member]
Debt Instrument, Term (Year)	5 years
Commitments to Originate Fixed Rate Mortgages [Member]
Other Commitment, Total	$ 32,095,000	$ 6,690,000
Commitment, Mortgage Loan Origination, Disbursed Period (Day)	30 days

The period in which a majority of the mortgage loans being originated were disbursed.

No definition available.

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- Definition

Amount of commission revenue from buying and selling securities on behalf of customers.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 05
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=68070981&loc=d3e40544-110947

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(a),(b))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

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- Details

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- Details

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