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	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Loans	$ 885,850		$ 885,850		$ 958,488
Write off	2,089	$ 1,917	5,789	$ 4,542
Nonaccrual	209		209		146
Financial Asset, Not Past Due [Member]
Loans	877,895		877,895		949,456
Financial Asset, 30 to 59 Days Past Due [Member]
Loans	5,457		5,457		6,158
Financial Asset, 60 to 89 Days Past Due [Member]
Loans	1,260		1,260		2,100
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans	1,029		1,029		628
Commercial Portfolio Segment [Member]
Originated prior	21,511		21,511		23,903
Originated four years before	7,611		7,611		5,549
Originated three years before	13,435		13,435		12,557
Originated two years before	37,614		37,614		17,293
Originated one years before	23,546		23,546		53,928
Originated current year	12,029		12,029		23,966
Total Term Loans	115,746		115,746		137,196
Revolving Loans Amortized Cost Basis	19,829		19,829		32,421
Loans	135,575		135,575		169,617
Prior, write off	0		0
Four years before. write off	0		0
Three years before, write off	3		3
Two years before, write off	135		135
One year before, write off	0		0
Current, write off	0		0
Term loan, write off	138		138
Revolving, writeoff	124		272
Write off	262	(0)	410	20
Nonaccrual	0		0		50
Commercial Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member]
Loans	135,477		135,477		169,337
Commercial Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Loans	0		0		172
Commercial Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Loans	25		25		58
Commercial Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans	73		73		0
Construction Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	5,043		5,043		3,088
Loans	5,043		5,043		3,088
Prior, write off	0		0
Four years before. write off	0		0
Three years before, write off	0		0
Two years before, write off	0		0
One year before, write off	0		0
Current, write off	0		0
Term loan, write off	0		0
Revolving, writeoff	0		0
Write off	(0)	(0)	0	(0)
Nonaccrual	0		0		0
Construction Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member]
Loans	5,043		5,043		3,088
Construction Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Loans	0		0		0
Construction Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Loans	0		0		0
Construction Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans	0		0		0
Commercial Real Estate Portfolio Segment [Member]
Originated prior	193,210		193,210		154,671
Originated four years before	69,870		69,870		58,473
Originated three years before	70,828		70,828		73,552
Originated two years before	69,569		69,569		74,822
Originated one years before	51,476		51,476		71,618
Originated current year	39,329		39,329		57,971
Total Term Loans	494,282		494,282		491,107
Revolving Loans Amortized Cost Basis	0		0		0
Loans	494,282		494,282		491,107
Prior, write off	0		0
Four years before. write off	0		0
Three years before, write off	0		0
Two years before, write off	0		0
One year before, write off	0		0
Current, write off	0		0
Term loan, write off	0		0
Revolving, writeoff	0		0
Write off	(0)	(0)	0	(0)
Nonaccrual	192		192		53
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member]
Loans	493,537		493,537		490,354
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Loans	443		443		508
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Loans	110		110		192
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans	0		0		0
Residential Portfolio Segment [Member]
Originated prior	11,283		11,283		13,834
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	11,283		11,283		13,834
Revolving Loans Amortized Cost Basis	0		0		0
Loans	11,283		11,283		13,834
Prior, write off	0		0
Four years before. write off	0		0
Three years before, write off	0		0
Two years before, write off	0		0
One year before, write off	0		0
Current, write off	0		0
Term loan, write off	0		0
Revolving, writeoff	0		0
Write off	(0)	(0)	0	(0)
Nonaccrual	3		3		27
Residential Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member]
Loans	11,280		11,280		13,430
Residential Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Loans	0		0		377
Residential Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Loans	0		0		0
Residential Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans	0		0		0
Consumer Portfolio Segment [Member]
Originated prior	9,117		9,117
Originated four years before	14,726		14,726
Originated three years before	26,267		26,267
Originated two years before	59,699		59,699
Originated one years before	79,640		79,640
Originated current year	32,363		32,363
Revolving Loans Amortized Cost Basis	17,855		17,855
Loans	239,667		239,667		280,842
Prior, write off	43		208
Four years before. write off	18		135
Three years before, write off	209		717
Two years before, write off	618		1,529
One year before, write off	672		2,414
Current, write off	177		177
Term loan, write off	1,737		5,180
Revolving, writeoff	90		199
Write off	1,827	$ 1,917	5,379	$ 4,522
Financing Receivable, Term Loan	221,812		221,812
Nonaccrual	14		14		16
Consumer Portfolio Segment [Member] \| Term Loan Originated Prior [Member]
Loans					6,179
Nonaccrual	0		0		0
Consumer Portfolio Segment [Member] \| Term Loans Originated in 2018 [Member]
Loans					13,500
Nonaccrual					0
Consumer Portfolio Segment [Member] \| Term Loans Originated in 2019 [Member]
Loans					22,985
Nonaccrual	0		0		0
Consumer Portfolio Segment [Member] \| Term Loans Originated in 2020 [Member]
Loans					37,133
Nonaccrual	0		0		0
Consumer Portfolio Segment [Member] \| Term Loans Originated in 2021 [Member]
Loans					78,754
Nonaccrual	0		0		0
Consumer Portfolio Segment [Member] \| Term Loans Originated in 2022 [Member]
Loans					101,764
Nonaccrual	0		0		0
Consumer Portfolio Segment [Member] \| Total Term Loans [Member]
Loans					260,315
Nonaccrual	0		0		0
Consumer Portfolio Segment [Member] \| Revolving Loans Amortized Cost Basis [Member]
Loans					20,527
Nonaccrual	14		14		16
Consumer Portfolio Segment [Member] \| Term Loans Originated in 2023 [Member]
Nonaccrual	0		0
Consumer Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member]
Originated prior	8,841		8,841
Originated four years before	14,395		14,395
Originated three years before	25,746		25,746
Originated two years before	56,758		56,758
Originated one years before	77,347		77,347
Originated current year	31,708		31,708
Revolving Loans Amortized Cost Basis	17,763		17,763
Loans	232,558		232,558		273,247
Financing Receivable, Term Loan	214,795		214,795
Consumer Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member] \| Term Loan Originated Prior [Member]
Loans					6,017
Consumer Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member] \| Term Loans Originated in 2018 [Member]
Loans					13,147
Consumer Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member] \| Term Loans Originated in 2019 [Member]
Loans					22,330
Consumer Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member] \| Term Loans Originated in 2020 [Member]
Loans					35,783
Consumer Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member] \| Term Loans Originated in 2021 [Member]
Loans					76,126
Consumer Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member] \| Term Loans Originated in 2022 [Member]
Loans					99,414
Consumer Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member] \| Total Term Loans [Member]
Loans					252,817
Consumer Portfolio Segment [Member] \| Financial Asset, Not Past Due [Member] \| Revolving Loans Amortized Cost Basis [Member]
Loans					20,430
Consumer Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Originated prior	235		235
Originated four years before	280		280
Originated three years before	331		331
Originated two years before	2,006		2,006
Originated one years before	1,736		1,736
Originated current year	399		399
Revolving Loans Amortized Cost Basis	27		27
Loans	5,014		5,014		5,101
Financing Receivable, Term Loan	4,987		4,987
Consumer Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member] \| Term Loan Originated Prior [Member]
Loans					117
Consumer Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member] \| Term Loans Originated in 2018 [Member]
Loans					268
Consumer Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member] \| Term Loans Originated in 2019 [Member]
Loans					572
Consumer Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member] \| Term Loans Originated in 2020 [Member]
Loans					1,014
Consumer Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member] \| Term Loans Originated in 2021 [Member]
Loans					1,709
Consumer Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member] \| Term Loans Originated in 2022 [Member]
Loans					1,359
Consumer Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member] \| Total Term Loans [Member]
Loans					5,039
Consumer Portfolio Segment [Member] \| Financial Asset, 30 to 59 Days Past Due [Member] \| Revolving Loans Amortized Cost Basis [Member]
Loans					62
Consumer Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Originated prior	14		14
Originated four years before	12		12
Originated three years before	114		114
Originated two years before	512		512
Originated one years before	382		382
Originated current year	84		84
Revolving Loans Amortized Cost Basis	7		7
Loans	1,125		1,125		1,850
Financing Receivable, Term Loan	1,118		1,118
Consumer Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member] \| Term Loan Originated Prior [Member]
Loans					42
Consumer Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member] \| Term Loans Originated in 2018 [Member]
Loans					65
Consumer Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member] \| Term Loans Originated in 2019 [Member]
Loans					67
Consumer Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member] \| Term Loans Originated in 2020 [Member]
Loans					275
Consumer Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member] \| Term Loans Originated in 2021 [Member]
Loans					635
Consumer Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member] \| Term Loans Originated in 2022 [Member]
Loans					750
Consumer Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member] \| Total Term Loans [Member]
Loans					1,834
Consumer Portfolio Segment [Member] \| Financial Asset, 60 to 89 Days Past Due [Member] \| Revolving Loans Amortized Cost Basis [Member]
Loans					16
Consumer Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Originated prior	27		27
Originated four years before	39		39
Originated three years before	76		76
Originated two years before	423		423
Originated one years before	175		175
Originated current year	172		172
Revolving Loans Amortized Cost Basis	44		44
Loans	956		956		628
Financing Receivable, Term Loan	912		912
Consumer Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member] \| Term Loan Originated Prior [Member]
Loans					3
Consumer Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member] \| Term Loans Originated in 2018 [Member]
Loans					20
Consumer Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member] \| Term Loans Originated in 2019 [Member]
Loans					16
Consumer Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member] \| Term Loans Originated in 2020 [Member]
Loans					61
Consumer Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member] \| Term Loans Originated in 2021 [Member]
Loans					284
Consumer Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member] \| Term Loans Originated in 2022 [Member]
Loans					241
Consumer Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member] \| Total Term Loans [Member]
Loans					625
Consumer Portfolio Segment [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member] \| Revolving Loans Amortized Cost Basis [Member]
Loans					3
Pass [Member]
Loans	863,149		863,149		941,650
Pass [Member] \| Commercial Portfolio Segment [Member]
Originated prior	21,499		21,499		23,891
Originated four years before	5,086		5,086		5,549
Originated three years before	13,435		13,435		12,557
Originated two years before	34,779		34,779		17,293
Originated one years before	23,546		23,546		53,928
Originated current year	11,429		11,429		23,966
Total Term Loans	109,774		109,774		137,184
Revolving Loans Amortized Cost Basis	18,618		18,618		31,856
Loans	128,392		128,392		169,040
Pass [Member] \| Construction Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	5,043		5,043		3,088
Loans	5,043		5,043		3,088
Pass [Member] \| Commercial Real Estate Portfolio Segment [Member]
Originated prior	183,073		183,073		146,588
Originated four years before	69,055		69,055		58,473
Originated three years before	70,037		70,037		71,440
Originated two years before	69,569		69,569		74,016
Originated one years before	51,476		51,476		71,618
Originated current year	39,329		39,329		55,707
Total Term Loans	482,539		482,539		477,842
Revolving Loans Amortized Cost Basis	0		0		0
Loans	482,539		482,539		477,842
Pass [Member] \| Residential Portfolio Segment [Member]
Originated prior	10,943		10,943		13,457
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	10,943		10,943		13,457
Revolving Loans Amortized Cost Basis	0		0		0
Loans	10,943		10,943		13,457
Pass [Member] \| Consumer Portfolio Segment [Member]
Loans	236,232		236,232		278,223
Substandard [Member]
Loans	20,129		20,129		15,298
Substandard [Member] \| Commercial Portfolio Segment [Member]
Originated prior	12		12		12
Originated four years before	2,525		2,525		0
Originated three years before	0		0		0
Originated two years before	2,835		2,835		0
Originated one years before	0		0		0
Originated current year	600		600		0
Total Term Loans	5,972		5,972		12
Revolving Loans Amortized Cost Basis	1,211		1,211		565
Loans	7,183		7,183		577
Substandard [Member] \| Construction Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	0		0		0
Loans	0		0		0
Substandard [Member] \| Commercial Real Estate Portfolio Segment [Member]
Originated prior	10,137		10,137		8,083
Originated four years before	815		815		0
Originated three years before	791		791		2,112
Originated two years before	0		0		806
Originated one years before	0		0		0
Originated current year	0		0		2,264
Total Term Loans	11,743		11,743		13,265
Revolving Loans Amortized Cost Basis	0		0		0
Loans	11,743		11,743		13,265
Substandard [Member] \| Residential Portfolio Segment [Member]
Originated prior	340		340		377
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	340		340		377
Revolving Loans Amortized Cost Basis	0		0		0
Loans	340		340		377
Substandard [Member] \| Consumer Portfolio Segment [Member]
Loans	863		863		1,079
Doubtful [Member]
Loans	1,422		1,422		752
Doubtful [Member] \| Commercial Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	0		0		0
Loans	0		0		0
Doubtful [Member] \| Construction Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	0		0		0
Loans	0		0		0
Doubtful [Member] \| Commercial Real Estate Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	0		0		0
Loans	0		0		0
Doubtful [Member] \| Residential Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	0		0		0
Loans	0		0		0
Doubtful [Member] \| Consumer Portfolio Segment [Member]
Loans	1,422		1,422		752
Unlikely to be Collected Financing Receivable [Member]
Loans	1,150		1,150		788
Unlikely to be Collected Financing Receivable [Member] \| Commercial Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	0		0		0
Loans	0		0		0
Unlikely to be Collected Financing Receivable [Member] \| Construction Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	0		0		0
Loans	0		0		0
Unlikely to be Collected Financing Receivable [Member] \| Commercial Real Estate Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	0		0		0
Loans	0		0		0
Unlikely to be Collected Financing Receivable [Member] \| Residential Portfolio Segment [Member]
Originated prior	0		0		0
Originated four years before	0		0		0
Originated three years before	0		0		0
Originated two years before	0		0		0
Originated one years before	0		0		0
Originated current year	0		0		0
Total Term Loans	0		0		0
Revolving Loans Amortized Cost Basis	0		0		0
Loans	0		0		0
Unlikely to be Collected Financing Receivable [Member] \| Consumer Portfolio Segment [Member]
Loans	$ 1,150		$ 1,150		$ 788

Amount of writeoff of financing receivable, charged against allowance for credit loss.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479294/326-20-55-79

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-SubTopic 10
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-11B

+ Details

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