Note 3 - Loans and Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Individually evaluated for impairment	$ 0		$ 0		$ 7
Collectively evaluated for impairment	6,566		6,566		6,045
Allowance for loan losses	6,566	$ 6,567	6,566	$ 6,567	6,083
Beginning balance	6,394	6,637	6,083	6,625
Provision for loan losses	175	0	550	75
Charge-offs	(77)	(141)	(287)	(328)
Recoveries	74	71	220	195
Ending balance	6,566	6,567	6,566	6,567
Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0		31
Beginning balance			31
Ending balance	0		0
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	1,352		1,352		1,143
Allowance for loan losses	1,352	1,211	1,352	1,211	1,174
Beginning balance	1,265	1,216	1,174	1,239
Provision for loan losses	87	20	169	0
Charge-offs	0	(26)	(1)	(29)
Recoveries	0	1	10	1
Ending balance	1,352	1,211	1,352	1,211
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0		31
Beginning balance			31
Ending balance	0		0
Real Estate Mortgage Portfolio Segment [Member] \| Land Loan [Member]
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	273		273		234
Allowance for loan losses	273	205	273	205	234
Beginning balance	241	215	234	209
Provision for loan losses	32	(4)	39	5
Charge-offs	0	(6)	0	(9)
Recoveries	0	0	0	0
Ending balance	273	205	273	205
Real Estate Mortgage Portfolio Segment [Member] \| Land Loan [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0		0
Beginning balance			0
Ending balance	0		0
Real Estate Mortgage Portfolio Segment [Member] \| Construction Loans [Member]
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	430		430		403
Allowance for loan losses	430	403	430	403	403
Beginning balance	496	389	403	292
Provision for loan losses	(66)	14	27	111
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	430	403	430	403
Real Estate Mortgage Portfolio Segment [Member] \| Construction Loans [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0		0
Beginning balance			0
Ending balance	0		0
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Real Estate Loan [Member]
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	2,070		2,070		1,884
Allowance for loan losses	2,070	2,317	2,070	2,317	1,884
Beginning balance	1,991	2,357	1,884	2,358
Provision for loan losses	79	(40)	186	(41)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Ending balance	2,070	2,317	2,070	2,317
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Real Estate Loan [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0		0
Beginning balance			0
Ending balance	0		0
Commercial Portfolio Segment [Member]
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	886		886		873
Allowance for loan losses	886	764	886	764	873
Beginning balance	888	784	873	843
Provision for loan losses	(2)	(30)	13	(89)
Charge-offs	0	0	(9)	0
Recoveries	0	10	9	10
Ending balance	886	764	886	764
Commercial Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0		0
Beginning balance			0
Ending balance	0		0
Consumer Portfolio Segment [Member]
Allowance for loan losses	1,019		1,019		988
Beginning balance	980		988
Provision for loan losses	42		109
Charge-offs	(77)		(277)
Recoveries	74		199
Ending balance	1,019		1,019
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member]
Individually evaluated for impairment	0		0		7
Collectively evaluated for impairment	536		536		520
Allowance for loan losses	536	645	536	645	527
Beginning balance	533	625	527	617
Provision for loan losses	3	20	7	37
Charge-offs	0	0	0	(10)
Recoveries	0	0	2	1
Ending balance	536	645	536	645
Consumer Portfolio Segment [Member] \| Home Equity and Second Mortgage [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Allowance for loan losses	0		0		0
Beginning balance			0
Ending balance	0		0
Consumer Portfolio Segment [Member] \| All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	1,019		1,019		988
Allowance for loan losses	1,019	1,022	1,019	1,022	988
Beginning balance		1,051	988	1,067
Provision for loan losses		20		52
Charge-offs		(109)		(280)
Recoveries		60		183
Ending balance	1,019	$ 1,022	1,019	$ 1,022
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		$ 0
Beginning balance			0
Ending balance	$ 0		$ 0

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

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