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Note 2 - Loans and Allowance for Credit Losses - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	$ 10,047	$ 10,047	$ 9,892	$ 10,422	$ 10,262
Loans, individually evaluated		10,030	8,802
Loans, collectively evaluated		1,005,382	991,124
Loans		1,015,412	999,926
Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	138		106
Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	9,909		9,786
Real Estate Construction Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	671	671	337		350
Loans, individually evaluated		0	0
Loans, collectively evaluated		72,220	40,694
Loans		72,220	40,694
Real Estate Construction Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	0		0
Real Estate Construction Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	671		337
Consumer Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	3,816	3,816	3,823	3,936	3,945
Loans, individually evaluated		639	465
Loans, collectively evaluated		329,565	328,188
Loans		330,204	328,653
Consumer Real Estate Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	35		26
Consumer Real Estate Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	3,781		3,797
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	3,834	3,834	3,805	4,435	4,320
Loans, individually evaluated		9,391	8,337
Loans, collectively evaluated		446,790	459,446
Loans		456,181	467,783
Commercial Real Estate Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	103		80
Commercial Real Estate Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	3,731		3,725
Commercial Non Real Estate Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	674	674	849	625	658
Loans, individually evaluated		0	0
Loans, collectively evaluated		49,616	52,018
Loans		49,616	52,018
Commercial Non Real Estate Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	0		0
Commercial Non Real Estate Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	674		849
Public Sector and IDA Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	325	325	308	323	338
Loans, individually evaluated		0	0
Loans, collectively evaluated		62,124	63,677
Loans		62,124	63,677
Public Sector and IDA Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	0		0
Public Sector and IDA Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	325		308
Consumer Non Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	727	727	770	$ 737	$ 651
Loans, individually evaluated		0	0
Loans, collectively evaluated		45,067	47,101
Loans		$ 45,067	47,101
Consumer Non Real Estate Portfolio Segment [Member] \| Individually Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	0		0
Consumer Non Real Estate Portfolio Segment [Member] \| Collectively Evaluated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses	$ 727		$ 770