Note 3 - Loans and Allowance for Loan Losses - Troubled Debt Restructuring by Accrual Status (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Recorded investment in loans	$ 549,696	$ 490,830
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Recorded investment in loans	154,219	131,152
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Recorded investment in loans	161,503	138,141
Commercial Portfolio Segment [Member]
Recorded investment in loans	54,877	51,921
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Recorded investment in loans	60,060	55,742
Nonperforming Financial Instruments [Member]
TDR accruing	728	975
TDR nonaccrual	296	287
Recorded investment in loans	1,024	1,262
TDR related allowance for loan losses	0	7
Nonperforming Financial Instruments [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
TDR accruing	109	216
TDR nonaccrual	16	0
Recorded investment in loans	125	216
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	472	585
TDR nonaccrual	0	0
Recorded investment in loans	472	585
TDR related allowance for loan losses	0	0
Nonperforming Financial Instruments [Member] \| Commercial Portfolio Segment [Member]
TDR accruing	147	174
TDR nonaccrual	0	0
Recorded investment in loans	147	174
TDR related allowance for loan losses	0	0
Nonperforming Financial Instruments [Member] \| Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
TDR accruing	0	0
TDR nonaccrual	280	287
Recorded investment in loans	280	287
TDR related allowance for loan losses	$ 0	$ 7

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
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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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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