Note 3 - Loans and Allowance for Loan Losses - Troubled Debt Restructuring by Accrual Status (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Recorded investment in loans	$ 492,969	$ 508,879
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Recorded investment in loans	130,184	131,850
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Recorded investment in loans	132,626	135,484
Commercial Portfolio Segment [Member]
Recorded investment in loans	67,458	81,809
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Recorded investment in loans	51,092	53,277
Nonperforming Financial Instruments [Member]
TDR accruing	1,388	1,732
TDR nonaccrual	288	0
Recorded investment in loans	1,676	1,732
TDR related allowance for loan losses	7	0
Nonperforming Financial Instruments [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
TDR accruing	548	556
TDR nonaccrual	0	0
Recorded investment in loans	548	556
TDR related allowance for loan losses	0	0
Nonperforming Financial Instruments [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
TDR accruing	603	621
TDR nonaccrual	0	0
Recorded investment in loans	603	621
TDR related allowance for loan losses	0	0
Nonperforming Financial Instruments [Member] \| Commercial Portfolio Segment [Member]
TDR accruing	189	210
TDR nonaccrual	0	0
Recorded investment in loans	189	210
TDR related allowance for loan losses	0	0
Nonperforming Financial Instruments [Member] \| Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
TDR accruing	48	345
TDR nonaccrual	288	0
Recorded investment in loans	336	345
TDR related allowance for loan losses	$ 7	$ 0

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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+ References

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