Note 4 - Loans and Allowance for Credit Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Allowance for loan losses			$ 4,260	$ 4,284	$ 4,284
Provision for loan losses			622	44
Charge-offs	$ (290)	$ 0	(646)	(156)	(162)
Charge-offs	290	(0)	646	156	162
Recoveries	6	6	21	19	24
Allowance for loan losses	4,257	4,191	4,257	4,191	4,260
Allowance for loan losses ending balance evaluated for impairment individually	0	392	0	392	360
Allowance for loan losses ending balance evaluated for impairment collectively	4,257	3,799	4,257	3,799	3,899
Outstanding loan balances evaluated for impairment individually	0	2,713	0	2,713	2,710
Outstanding loan balances evaluated for impairment collectively	627,764	573,699	627,764	573,699	585,252
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Provision for loan losses					114
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses			2,481	2,448	2,448
Provision for loan losses			448	(12)	33
Charge-offs			(646)	0	0
Charge-offs			646	0	0
Recoveries			0	0	0
Allowance for loan losses	2,283	2,436	2,283	2,436	2,481
Allowance for loan losses ending balance evaluated for impairment individually	0	392	0	392	360
Allowance for loan losses ending balance evaluated for impairment collectively	2,283	2,044	2,283	2,044	2,122
Outstanding loan balances evaluated for impairment individually	0	2,441	0	2,441	2,440
Outstanding loan balances evaluated for impairment collectively	430,518	383,354	430,518	383,354	395,686
Construction and Land Development [Member]
Allowance for loan losses			478	253	253
Provision for loan losses			42	162	225
Charge-offs			0	0	0
Charge-offs			0	0	0
Recoveries			0	0	0
Allowance for loan losses	520	415	520	415	478
Allowance for loan losses ending balance evaluated for impairment individually	0	0	0	0	0
Allowance for loan losses ending balance evaluated for impairment collectively	520	415	520	415	478
Outstanding loan balances evaluated for impairment individually	0	0	0	0	0
Outstanding loan balances evaluated for impairment collectively	34,217	30,328	34,217	30,328	27,357
Residential Portfolio Segment [Member]
Allowance for loan losses			751	1,013	1,013
Provision for loan losses			(130)	(255)	(281)
Charge-offs			0	0	(5)
Charge-offs			0	0	5
Recoveries			21	19	24
Allowance for loan losses	642	777	642	777	751
Allowance for loan losses ending balance evaluated for impairment individually	0	0	0	0	0
Allowance for loan losses ending balance evaluated for impairment collectively	642	777	642	777	751
Outstanding loan balances evaluated for impairment individually	0	272	0	272	270
Outstanding loan balances evaluated for impairment collectively	111,032	108,931	111,032	108,931	111,628
Commercial Portfolio Segment [Member]
Allowance for loan losses			513	494	494
Provision for loan losses			249	200	171
Charge-offs			0	(153)	(152)
Charge-offs			0	153	152
Recoveries			0	0	0
Allowance for loan losses	762	541	762	541	513
Allowance for loan losses ending balance evaluated for impairment individually	0	0	0	0	0
Allowance for loan losses ending balance evaluated for impairment collectively	762	541	762	541	512
Outstanding loan balances evaluated for impairment individually	0	0	0	0	0
Outstanding loan balances evaluated for impairment collectively	51,864	50,932	51,864	50,932	50,405
Consumer Portfolio Segment [Member]
Allowance for loan losses			4	2	2
Provision for loan losses			(3)	3	7
Charge-offs			0	(3)	(5)
Charge-offs			0	3	5
Recoveries			0	0	0
Allowance for loan losses	1	2	1	2	4
Allowance for loan losses ending balance evaluated for impairment individually	0	0	0	0	0
Allowance for loan losses ending balance evaluated for impairment collectively	1	2	1	2	4
Outstanding loan balances evaluated for impairment individually	0	0	0	0	0
Outstanding loan balances evaluated for impairment collectively	133	154	133	154	176
Unallocated Financing Receivables [Member]
Allowance for loan losses			33	74	74
Provision for loan losses			16	(54)	(41)
Charge-offs			0	0	0
Charge-offs			(0)	0	(0)
Recoveries			0	0	0
Allowance for loan losses	49	20	49	20	33
Allowance for loan losses ending balance evaluated for impairment individually	0	0	0	0	0
Allowance for loan losses ending balance evaluated for impairment collectively	49	20	49	20	33
Outstanding loan balances evaluated for impairment individually	0	0	0	0	0
Outstanding loan balances evaluated for impairment collectively	$ 0	$ 0	$ 0	$ 0	$ 0

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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