Note 9 - Allowance for Loan Losses and Credit Quality Information - Impaired Loans and Related Allowances (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Related allowance	$ 442		$ 406
Recorded investment	4,559		4,650
Unpaid principal balance	4,578		4,669
Average recorded investment	4,606	$ 3,043
Interest income recognized	5	7
Residential Portfolio Segment [Member]
Recorded investment, with no related allowance	394		253
Unpaid principal balance, with no related allowance	413		272
Recorded investment, with related allowance	84		87
Unpaid principal balance, with related allowance	84		87
Related allowance	34		36
Recorded investment	478		340
Unpaid principal balance	497		359
Average recorded investment, with no related allowance	324	739
Interest income recognized, with no related allowance	2	6
Average recorded investment, with related allowance	86	116
Interest income recognized, with related allowance	0	0
Average recorded investment	410	855
Interest income recognized	2	6
Commercial Real Estate Portfolio Segment [Member]
Related allowance	280		280
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Recorded investment, with no related allowance	185		189
Unpaid principal balance, with no related allowance	185		189
Recorded investment, with related allowance	3,366		3,568
Unpaid principal balance, with related allowance	3,366		3,568
Related allowance	280		280
Recorded investment	3,551		3,757
Unpaid principal balance	3,551		3,757
Average recorded investment, with no related allowance	187	205
Interest income recognized, with no related allowance	0	0
Average recorded investment, with related allowance	3,467	157
Interest income recognized, with related allowance	0	0
Average recorded investment	3,654	362
Interest income recognized	0	0
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member]
Average recorded investment, with no related allowance	0	1,002
Interest income recognized, with no related allowance	0	0
Average recorded investment, with related allowance	0	83
Interest income recognized, with related allowance	0	0
Average recorded investment	0	1,085
Interest income recognized	0	0
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance	359		419
Unpaid principal balance, with no related allowance	359		419
Recorded investment, with related allowance	164		127
Unpaid principal balance, with related allowance	164		127
Related allowance	121		83
Recorded investment	523		546
Unpaid principal balance	523		546
Average recorded investment, with no related allowance	389	543
Interest income recognized, with no related allowance	2	1
Average recorded investment, with related allowance	146	162
Interest income recognized, with related allowance	1	0
Average recorded investment	535	705
Interest income recognized	3	1
Commercial Portfolio Segment [Member]
Recorded investment, with related allowance	7		7
Unpaid principal balance, with related allowance	7		7
Related allowance	7		7
Recorded investment	7		7
Unpaid principal balance	7		$ 7
Average recorded investment, with related allowance	7	36
Interest income recognized, with related allowance	0	0
Average recorded investment	7	36
Interest income recognized	$ 0	$ 0

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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- Definition

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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