Note 5 - Allowance for Credit Losses - Credit Rating (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Loans, originated current year	$ 97,812		$ 69,927
Loans, originated one years before	123,525		58,487
Loans, originated two years before	91,844		50,268
Loans, originated three years before	127,323		74,366
Loans, originated four years before	137,579		39,835
Loans, originated prior	236,872		91,369
Loans, revolving	86,669		52,906
Loans, before fees	901,624		437,158
Loans, write-off	97	$ 37	62
Commercial Portfolio Segment [Member]
Loans, originated current year	4,512		6,964
Loans, originated one years before	15,846		4,881
Loans, originated two years before	7,930		6,221
Loans, originated three years before	11,961		14,788
Loans, originated four years before	34,618		4,419
Loans, originated prior	31,969		4,812
Loans, revolving	54,859		45,905
Loans, before fees	161,695		87,990
Loans, originated current year, write-off	0		0
Loans, originated one years before, write-off	0		0
Loans, originated two years before, write-off	25		0
Loans, originated three years before, write-off	0		0
Loans, originated four years before, write-off	0		0
Loans, originated prior, write-off	0		0
Loans, revolving, write-off	0		0
Loans, write-off	25	(0)	0
Commercial Portfolio Segment [Member] | Pass [Member]
Loans, originated current year	4,512		6,909
Loans, originated one years before	15,794		4,500
Loans, originated two years before	7,520		6,221
Loans, originated three years before	10,861		14,788
Loans, originated four years before	33,798		3,968
Loans, originated prior	30,392		4,812
Loans, revolving	53,681		45,006
Loans, before fees	156,558		86,204
Commercial Portfolio Segment [Member] | Special Mention [Member]
Loans, originated current year	0		55
Loans, originated one years before	52		381
Loans, originated two years before	361		0
Loans, originated three years before	0		0
Loans, originated four years before	820		451
Loans, originated prior	1,577		0
Loans, revolving	988		899
Loans, before fees	3,798		1,786
Commercial Portfolio Segment [Member] | Substandard [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	49		0
Loans, originated three years before	1,100		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	190		0
Loans, before fees	1,339		0
Commercial Portfolio Segment [Member] | Doubtful [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Commercial Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Commercial Real Estate Portfolio Segment [Member]
Loans, originated current year	45,768		44,673
Loans, originated one years before	56,386		35,812
Loans, originated two years before	41,515		27,374
Loans, originated three years before	55,668		38,885
Loans, originated four years before	51,051		16,420
Loans, originated prior	72,111		49,375
Loans, revolving	19,096		56
Loans, before fees	341,595		212,595
Loans, originated current year, write-off	0		0
Loans, originated one years before, write-off	0		0
Loans, originated two years before, write-off	0		0
Loans, originated three years before, write-off	0		0
Loans, originated four years before, write-off	0		0
Loans, originated prior, write-off	0		0
Loans, revolving, write-off	0		0
Loans, write-off	0	(0)	0
Commercial Real Estate Portfolio Segment [Member] | Pass [Member]
Loans, originated current year	45,768		44,433
Loans, originated one years before	56,386		35,523
Loans, originated two years before	41,221		26,801
Loans, originated three years before	55,104		34,436
Loans, originated four years before	49,348		16,420
Loans, originated prior	67,409		46,684
Loans, revolving	17,287		56
Loans, before fees	332,523		204,353
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member]
Loans, originated current year	0		240
Loans, originated one years before	0		289
Loans, originated two years before	289		573
Loans, originated three years before	564		0
Loans, originated four years before	1,703		0
Loans, originated prior	4,359		2,677
Loans, revolving	9		0
Loans, before fees	6,924		3,779
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	5		0
Loans, originated three years before	0		4,449
Loans, originated four years before	0		0
Loans, originated prior	343		14
Loans, revolving	1,800		0
Loans, before fees	2,148		4,463
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Commercial Real Estate Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Residential Portfolio Segment [Member] | Real Estate Loan [Member]
Loans, originated current year	40,275		14,892
Loans, originated one years before	43,087		15,209
Loans, originated two years before	36,767		15,320
Loans, originated three years before	55,755		20,287
Loans, originated four years before	49,467		18,859
Loans, originated prior	125,300		36,650
Loans, revolving	3,419		128
Loans, before fees	354,070		121,345
Loans, originated current year, write-off	0		0
Loans, originated one years before, write-off	0		0
Loans, originated two years before, write-off	0		0
Loans, originated three years before, write-off	0		0
Loans, originated four years before, write-off	0		0
Loans, originated prior, write-off	0		0
Loans, revolving, write-off	0		0
Loans, write-off	0	(0)	0
Residential Portfolio Segment [Member] | Home Equity Loan [Member]
Loans, originated current year	3,732		109
Loans, originated one years before	4,408		0
Loans, originated two years before	2,637		0
Loans, originated three years before	2,363		0
Loans, originated four years before	2,126		0
Loans, originated prior	7,182		369
Loans, revolving	8,776		6,708
Loans, before fees	31,224		7,186
Loans, originated current year, write-off	0		0
Loans, originated one years before, write-off	0		0
Loans, originated two years before, write-off	0		0
Loans, originated three years before, write-off	0		0
Loans, originated four years before, write-off	0		0
Loans, originated prior, write-off	0		0
Loans, revolving, write-off	0		0
Loans, write-off	0	(0)	0
Residential Portfolio Segment [Member] | Pass [Member] | Real Estate Loan [Member]
Loans, originated current year	40,275		14,439
Loans, originated one years before	42,822		14,932
Loans, originated two years before	36,379		15,320
Loans, originated three years before	55,729		19,923
Loans, originated four years before	49,367		18,859
Loans, originated prior	120,919		35,550
Loans, revolving	3,227		128
Loans, before fees	348,718		119,151
Residential Portfolio Segment [Member] | Pass [Member] | Home Equity Loan [Member]
Loans, originated current year	3,732		109
Loans, originated one years before	4,383		0
Loans, originated two years before	2,637		0
Loans, originated three years before	2,363		0
Loans, originated four years before	2,126		0
Loans, originated prior	7,151		369
Loans, revolving	8,776		6,708
Loans, before fees	31,168		7,186
Residential Portfolio Segment [Member] | Special Mention [Member] | Real Estate Loan [Member]
Loans, originated current year	0		453
Loans, originated one years before	265		277
Loans, originated two years before	191		0
Loans, originated three years before	0		364
Loans, originated four years before	100		0
Loans, originated prior	1,705		624
Loans, revolving	0		0
Loans, before fees	2,261		1,718
Residential Portfolio Segment [Member] | Special Mention [Member] | Home Equity Loan [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Residential Portfolio Segment [Member] | Substandard [Member] | Real Estate Loan [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	197		0
Loans, originated three years before	26		0
Loans, originated four years before	0		0
Loans, originated prior	2,676		476
Loans, revolving	192		0
Loans, before fees	3,091		476
Residential Portfolio Segment [Member] | Substandard [Member] | Home Equity Loan [Member]
Loans, originated current year	0		0
Loans, originated one years before	25		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	31		0
Loans, revolving	0		0
Loans, before fees	56		0
Residential Portfolio Segment [Member] | Doubtful [Member] | Real Estate Loan [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Residential Portfolio Segment [Member] | Doubtful [Member] | Home Equity Loan [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Residential Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Real Estate Loan [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Residential Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Home Equity Loan [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Consumer Portfolio Segment [Member] | Consumer, Other [Member]
Loans, originated current year	1,223		707
Loans, originated one years before	1,187		467
Loans, originated two years before	880		200
Loans, originated three years before	319		31
Loans, originated four years before	79		7
Loans, originated prior	235		5
Loans, revolving	519		109
Loans, before fees	4,442		1,526
Loans, originated current year, write-off	0		10
Loans, originated one years before, write-off	21		0
Loans, originated two years before, write-off	3		0
Loans, originated three years before, write-off	0		0
Loans, originated four years before, write-off	0		0
Loans, originated prior, write-off	0		0
Loans, revolving, write-off	0		0
Loans, write-off	24	10	10
Consumer Portfolio Segment [Member] | Automobile Loan [Member]
Loans, originated current year	2,302		2,582
Loans, originated one years before	2,611		2,118
Loans, originated two years before	2,115		1,153
Loans, originated three years before	1,257		375
Loans, originated four years before	238		130
Loans, originated prior	75		158
Loans, revolving	0		0
Loans, before fees	8,598		6,516
Loans, originated current year, write-off	0		13
Loans, originated one years before, write-off	36		26
Loans, originated two years before, write-off	6		0
Loans, originated three years before, write-off	6		13
Loans, originated four years before, write-off	0		0
Loans, originated prior, write-off	0		0
Loans, revolving, write-off	0		0
Loans, write-off	48	$ 27	52
Consumer Portfolio Segment [Member] | Pass [Member] | Consumer, Other [Member]
Loans, originated current year	1,223		707
Loans, originated one years before	1,185		445
Loans, originated two years before	857		200
Loans, originated three years before	307		31
Loans, originated four years before	79		7
Loans, originated prior	235		5
Loans, revolving	518		109
Loans, before fees	4,404		1,504
Consumer Portfolio Segment [Member] | Pass [Member] | Automobile Loan [Member]
Loans, originated current year	2,302		2,574
Loans, originated one years before	2,611		2,113
Loans, originated two years before	2,089		1,138
Loans, originated three years before	1,246		367
Loans, originated four years before	221		130
Loans, originated prior	75		155
Loans, revolving	0		0
Loans, before fees	8,544		6,477
Consumer Portfolio Segment [Member] | Special Mention [Member] | Consumer, Other [Member]
Loans, originated current year	0		0
Loans, originated one years before	1		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	1		0
Consumer Portfolio Segment [Member] | Special Mention [Member] | Automobile Loan [Member]
Loans, originated current year	0		8
Loans, originated one years before	0		5
Loans, originated two years before	26		15
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	26		28
Consumer Portfolio Segment [Member] | Substandard [Member] | Consumer, Other [Member]
Loans, originated current year	0		0
Loans, originated one years before	1		0
Loans, originated two years before	2		0
Loans, originated three years before	12		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	1		0
Loans, before fees	16		0
Consumer Portfolio Segment [Member] | Substandard [Member] | Automobile Loan [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	11		8
Loans, originated four years before	17		0
Loans, originated prior	0		3
Loans, revolving	0		0
Loans, before fees	28		11
Consumer Portfolio Segment [Member] | Doubtful [Member] | Consumer, Other [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		22
Loans, originated two years before	21		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	21		22
Consumer Portfolio Segment [Member] | Doubtful [Member] | Automobile Loan [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Consumer Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Consumer, Other [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	0		0
Consumer Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Automobile Loan [Member]
Loans, originated current year	0		0
Loans, originated one years before	0		0
Loans, originated two years before	0		0
Loans, originated three years before	0		0
Loans, originated four years before	0		0
Loans, originated prior	0		0
Loans, revolving	0		0
Loans, before fees	$ 0		$ 0