Note 4 - Loans, Allowance for Credit Losses and Other Real Estate Owned - Risk Category of Loans by Class (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Loans	$ 696,204		$ 726,482
Nonaccrual	1,165		1,474
Loans, Writeoff	791	$ 1,726
Financial Asset, Not Past Due [Member]
Loans	690,925		721,102
Financial Asset, 30 to 59 Days Past Due [Member]
Loans	3,392		2,910
Financial Asset, 60 to 89 Days Past Due [Member]
Loans	445		656
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans	277		340
Pass [Member]
Loans	684,766		714,020
Substandard [Member]
Loans	10,343		10,992
Doubtful [Member]
Loans	734		1,152
Unlikely to be Collected Financing Receivable [Member]
Loans	361		318
Commercial Portfolio Segment [Member]
Originated prior	22,807		20,293
Originated four years before	7,246		4,407
Originated three years before	6,040		8,072
Originated two years before	15,861		6,806
Originated one years before	31,174		16,560
Originated current year	1,748		37,067
Total Term Loans	84,876		93,205
Financing Receivable Revolving	23,600		23,804
Loans	108,476		117,009
Nonaccrual	785		1,095
Originated prior, writeoff	0		0
Originated four years before, writeoff	0		1,559
Originated three years before, writeoff	0		0
Originated two years before, writeoff	0		5
Originated one years before, writeoff	0		0
Originated current year, writeoff	0		0
Financing Receivable, before Allowance for Credit Loss and Revolving Loans, Writeoff	0		1,564
Financing Receivable Revolving, Writeoff	0		33
Loans, Writeoff	(0)	10	1,597
Commercial Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member]
Loans	107,447		115,595
Commercial Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Loans	244		295
Commercial Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Loans	0		24
Commercial Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans	0		0
Commercial Portfolio Segment [Member] \| Pass [Member]
Originated prior	22,620		20,092
Originated four years before	7,246		4,407
Originated three years before	6,040		8,072
Originated two years before	15,861		6,806
Originated one years before	30,197		16,560
Originated current year	1,748		35,914
Total Term Loans	83,712		91,851
Financing Receivable Revolving	23,123		23,010
Loans	106,835		114,861
Commercial Portfolio Segment [Member] \| Substandard [Member]
Originated prior	187		201
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	291		0
Originated current year	0		446
Total Term Loans	478		647
Financing Receivable Revolving	477		406
Loans	955		1,053
Commercial Portfolio Segment [Member] \| Doubtful [Member]
Originated prior	0		0
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	686		0
Originated current year	0		707
Total Term Loans	686		707
Financing Receivable Revolving	0		388
Loans	686		1,095
Commercial Portfolio Segment [Member] \| Unlikely to be Collected Financing Receivable [Member]
Originated prior	0		0
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	0		0
Originated current year	0		0
Total Term Loans	0		0
Financing Receivable Revolving	0		0
Loans	0		0
Commercial Real Estate Portfolio Segment [Member]
Originated prior	247,320		214,818
Originated four years before	45,739		55,247
Originated three years before	40,779		46,224
Originated two years before	67,722		41,080
Originated one years before	55,927		68,136
Originated current year	14,474		56,725
Total Term Loans	471,961		482,230
Financing Receivable Revolving	0		0
Loans	471,961		482,230
Nonaccrual	380		379
Originated prior, writeoff	0		191
Originated four years before, writeoff	0		0
Originated three years before, writeoff	0		0
Originated two years before, writeoff	0		0
Originated one years before, writeoff	0		0
Originated current year, writeoff	0		0
Financing Receivable, before Allowance for Credit Loss and Revolving Loans, Writeoff	0		191
Financing Receivable Revolving, Writeoff	0		0
Loans, Writeoff	(0)	191	191
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member]
Loans	469,992		481,664
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Loans	1,501		187
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Loans	88		0
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans	0		0
Commercial Real Estate Portfolio Segment [Member] \| Pass [Member]
Originated prior	239,495		206,896
Originated four years before	45,739		55,247
Originated three years before	40,779		46,224
Originated two years before	67,722		41,080
Originated one years before	55,927		68,136
Originated current year	14,474		56,557
Total Term Loans	464,136		474,140
Financing Receivable Revolving	0		0
Loans	464,136		474,140
Commercial Real Estate Portfolio Segment [Member] \| Substandard [Member]
Originated prior	7,825		7,922
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	0		0
Originated current year	0		168
Total Term Loans	7,825		8,090
Financing Receivable Revolving	0		0
Loans	7,825		8,090
Commercial Real Estate Portfolio Segment [Member] \| Doubtful [Member]
Originated prior	0		0
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	0		0
Originated current year	0		0
Total Term Loans	0		0
Financing Receivable Revolving	0		0
Loans	0		0
Commercial Real Estate Portfolio Segment [Member] \| Unlikely to be Collected Financing Receivable [Member]
Originated prior	0		0
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	0		0
Originated current year	0		0
Total Term Loans	0		0
Financing Receivable Revolving	0		0
Loans	0		0
Residential Portfolio Segment [Member]
Originated prior	6,601		7,186
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	0		0
Originated current year	0		0
Total Term Loans	6,601		7,186
Financing Receivable Revolving	0		0
Loans	6,601		7,186
Nonaccrual	0		0
Originated prior, writeoff	0		0
Originated four years before, writeoff	0		0
Originated three years before, writeoff	0		0
Originated two years before, writeoff	0		0
Originated one years before, writeoff	0		0
Originated current year, writeoff	0		0
Financing Receivable, before Allowance for Credit Loss and Revolving Loans, Writeoff	0		0
Financing Receivable Revolving, Writeoff	0		0
Loans, Writeoff	(0)	(0)	0
Residential Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member]
Loans	6,601		7,186
Residential Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Loans	0		0
Residential Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Loans	0		0
Residential Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans	0		0
Residential Portfolio Segment [Member] \| Pass [Member]
Originated prior	6,401		6,983
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	0		0
Originated current year	0		0
Total Term Loans	6,401		6,983
Financing Receivable Revolving	0		0
Loans	6,401		6,983
Residential Portfolio Segment [Member] \| Substandard [Member]
Originated prior	200		203
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	0		0
Originated current year	0		0
Total Term Loans	200		203
Financing Receivable Revolving	0		0
Loans	200		203
Residential Portfolio Segment [Member] \| Doubtful [Member]
Originated prior	0		0
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	0		0
Originated current year	0		0
Total Term Loans	0		0
Financing Receivable Revolving	0		0
Loans	0		0
Residential Portfolio Segment [Member] \| Unlikely to be Collected Financing Receivable [Member]
Originated prior	0		0
Originated four years before	0		0
Originated three years before	0		0
Originated two years before	0		0
Originated one years before	0		0
Originated current year	0		0
Total Term Loans	0		0
Financing Receivable Revolving	0		0
Loans	0		0
Consumer Portfolio Segment [Member]
Originated prior	19,782		6,214
Originated four years before	26,702		18,739
Originated three years before	16,226		30,929
Originated two years before	15,415		18,092
Originated one years before	13,526		17,164
Originated current year	4,029		15,035
Total Term Loans	95,680		106,173
Financing Receivable Revolving	13,486		13,884
Loans	109,166		120,057
Nonaccrual	0		0
Originated prior, writeoff	66		250
Originated four years before, writeoff	220		679
Originated three years before, writeoff	147		1,551
Originated two years before, writeoff	107		657
Originated one years before, writeoff	123		727
Originated current year, writeoff	0		10
Financing Receivable, before Allowance for Credit Loss and Revolving Loans, Writeoff	663		3,874
Financing Receivable Revolving, Writeoff	128		226
Loans, Writeoff	791	$ 1,525	4,100
Consumer Portfolio Segment [Member] \| Term Loan Originated Prior [Member]
Nonaccrual	0		0
Consumer Portfolio Segment [Member] \| Term Loans Originated Four Years Prior [Member]
Nonaccrual	0		0
Consumer Portfolio Segment [Member] \| Term Loans Originated Three Years Prior [Member]
Nonaccrual	0		0
Consumer Portfolio Segment [Member] \| Term Loans Originated Two Years Prior [Member]
Nonaccrual	0		0
Consumer Portfolio Segment [Member] \| Term Loans Originated One Year Prior [Member]
Nonaccrual	0		0
Consumer Portfolio Segment [Member] \| Term Loans Originated Current Year [Member]
Nonaccrual	0		0
Consumer Portfolio Segment [Member] \| Total Term Loans [Member]
Nonaccrual	0		0
Consumer Portfolio Segment [Member] \| Revolving Loans Amortized Cost Basis [Member]
Nonaccrual	0		0
Consumer Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member]
Originated prior	19,071		6,006
Originated four years before	25,991		17,795
Originated three years before	16,059		29,917
Originated two years before	15,166		17,712
Originated one years before	13,139		16,822
Originated current year	4,004		14,780
Total Term Loans	93,430		103,032
Financing Receivable Revolving	13,455		13,625
Loans	106,885		116,657
Consumer Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Originated prior	591		193
Originated four years before	563		804
Originated three years before	141		799
Originated two years before	183		270
Originated one years before	140		81
Originated current year	25		120
Total Term Loans	1,643		2,267
Financing Receivable Revolving	4		161
Loans	1,647		2,428
Consumer Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Originated prior	88		14
Originated four years before	60		103
Originated three years before	26		164
Originated two years before	33		41
Originated one years before	149		190
Originated current year	0		44
Total Term Loans	356		556
Financing Receivable Revolving	1		76
Loans	357		632
Consumer Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Originated prior	32		1
Originated four years before	88		37
Originated three years before	0		49
Originated two years before	33		69
Originated one years before	98		71
Originated current year	0		91
Total Term Loans	251		318
Financing Receivable Revolving	26		22
Loans	277		340
Consumer Portfolio Segment [Member] \| Pass [Member]
Loans	107,394		118,036
Consumer Portfolio Segment [Member] \| Substandard [Member]
Loans	1,363		1,646
Consumer Portfolio Segment [Member] \| Doubtful [Member]
Loans	48		57
Consumer Portfolio Segment [Member] \| Unlikely to be Collected Financing Receivable [Member]
Loans	$ 361		$ 318

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

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-Topic 326
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