Note 3 - Loans and Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Individually evaluated for impairment	$ 6		$ 7
Collectively evaluated for impairment	6,208		6,045
Allowance for loan losses	6,245	$ 6,628	6,083
Beginning balance	6,083	6,625
Provisions for loan losses	175	75
Charge-offs	(74)	(130)
Recoveries	61	58
Ending balance	6,245	6,628
Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	31		31
Beginning balance	31
Ending balance	31
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Individually evaluated for impairment	1		0
Collectively evaluated for impairment	1,196		1,143
Allowance for loan losses	1,228	1,221	1,174
Beginning balance	1,174	1,239
Provisions for loan losses	49	(14)
Charge-offs	0	(4)
Recoveries	5	0
Ending balance	1,228	1,221
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	31		31
Beginning balance	31
Ending balance	31
Real Estate Mortgage Portfolio Segment [Member] \| Land Loan [Member]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	235		234
Allowance for loan losses	235	209	234
Beginning balance	234	209
Provisions for loan losses	1	3
Charge-offs	0	(3)
Recoveries	0	0
Ending balance	235	209
Real Estate Mortgage Portfolio Segment [Member] \| Land Loan [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0
Beginning balance	0
Ending balance	0
Real Estate Mortgage Portfolio Segment [Member] \| Construction Loans [Member]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	387		403
Allowance for loan losses	387	348	403
Beginning balance	403	292
Provisions for loan losses	(16)	56
Charge-offs	0	0
Recoveries	0	0
Ending balance	387	348
Real Estate Mortgage Portfolio Segment [Member] \| Construction Loans [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0
Beginning balance	0
Ending balance	0
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	1,927		1,884
Allowance for loan losses	1,927	2,355	1,884
Beginning balance	1,884	2,358
Provisions for loan losses	43	(3)
Charge-offs	0	0
Recoveries	0	0
Ending balance	1,927	2,355
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Real Estate Loan [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0
Beginning balance	0
Ending balance	0
Commercial Portfolio Segment [Member]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	994		873
Allowance for loan losses	994	816	873
Beginning balance	873	843
Provisions for loan losses	121	(27)
Charge-offs	0	0
Recoveries	0	0
Ending balance	994	816
Commercial Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0
Beginning balance	0
Ending balance	0
Consumer Portfolio Segment [Member]
Provisions for loan losses	(13)
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Individually evaluated for impairment	5		7
Collectively evaluated for impairment	512		520
Allowance for loan losses	517	622	527
Beginning balance	527	617
Provisions for loan losses	(10)	14
Charge-offs	0	(9)
Recoveries	0	0
Ending balance	517	622
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0
Beginning balance	0
Ending balance	0
Consumer Portfolio Segment [Member] \| All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	957		988
Allowance for loan losses	957	1,057	988
Beginning balance	988	1,067
Provisions for loan losses		46
Charge-offs	(74)	(114)
Recoveries	56	58
Ending balance	957	$ 1,057
Consumer Portfolio Segment [Member] \| All Other Consumer Excluding Home Equity and Second Mortgage [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		$ 0
Beginning balance	0
Ending balance	$ 0

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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