Note 9 - Allowance for Loan Losses and Credit Quality Information - Impaired Loans and Related Allowances (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Related allowance	$ 148		$ 148		$ 406
Recorded investment	2,012		2,012		4,650
Unpaid principal balance	2,030		2,030		4,669
Average recorded investment	3,256	$ 1,860	3,929	$ 2,452
Interest income recognized	8	3	23	19
Residential Portfolio Segment [Member]
Recorded investment, with no related allowance	684		684		253
Unpaid principal balance, with no related allowance	702		702		272
Recorded investment, with related allowance	48		48		87
Unpaid principal balance, with related allowance	48		48		87
Related allowance	24		24		36
Recorded investment	732		732		340
Unpaid principal balance	750		750		359
Average recorded investment, with no related allowance	584	390	454	564
Interest income recognized, with no related allowance	1	0	8	4
Average recorded investment, with related allowance	65	122	75	119
Interest income recognized, with related allowance	0	0	0	0
Average recorded investment	649	512	529	683
Interest income recognized	1	0	8	4
Commercial Real Estate Portfolio Segment [Member]
Related allowance	0		0		280
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Recorded investment, with no related allowance	179		179		189
Unpaid principal balance, with no related allowance	179		179		189
Recorded investment, with related allowance	0		0		3,568
Unpaid principal balance, with related allowance	0		0		3,568
Related allowance	0		0		280
Recorded investment	179		179		3,757
Unpaid principal balance	179		179		3,757
Average recorded investment, with no related allowance	180	193	183	199
Interest income recognized, with no related allowance	5	0	7	0
Average recorded investment, with related allowance	1,643	168	2,555	163
Interest income recognized, with related allowance	0	0	0	0
Average recorded investment	1,823	361	2,738	362
Interest income recognized	5	0	7	0
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member]
Average recorded investment, with no related allowance		78		540
Interest income recognized, with no related allowance		0		0
Average recorded investment, with related allowance		163		123
Interest income recognized, with related allowance		0		7
Average recorded investment		241		663
Interest income recognized		0		7
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance	307		307		419
Unpaid principal balance, with no related allowance	307		307		419
Recorded investment, with related allowance	155		155		127
Unpaid principal balance, with related allowance	155		155		127
Related allowance	112		112		83
Recorded investment	462		462		546
Unpaid principal balance	462		462		546
Average recorded investment, with no related allowance	304	610	346	577
Interest income recognized, with no related allowance	2	0	7	6
Average recorded investment, with related allowance	157	114	151	138
Interest income recognized, with related allowance	0	3	1	1
Average recorded investment	461	724	497	715
Interest income recognized	2	3	8	7
Commercial Portfolio Segment [Member]
Recorded investment, with related allowance	639		639		7
Unpaid principal balance, with related allowance	639		639		7
Related allowance	12		12		7
Recorded investment	639		639		7
Unpaid principal balance	639		639		$ 7
Average recorded investment, with related allowance	323	22	165	29
Interest income recognized, with related allowance	0	0	0	1
Average recorded investment	323	22	165	29
Interest income recognized	$ 0	$ 0	$ 0	$ 1

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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