Note 9 - Allowance for Loan Losses and Credit Quality Information - Classified and Unclassified Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Loans receivable	$ 631,698	$ 653,791
Classified [Member]
Loans receivable	33,439	39,365
Classified [Member] | Special Mention [Member]
Loans receivable	21,702	20,026
Classified [Member] | Substandard [Member]
Loans receivable	11,572	19,160
Classified [Member] | Doubtful [Member]
Loans receivable	112	161
Classified [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans receivable	53	18
Unclassified [Member]
Loans receivable	598,259	614,426
Residential Portfolio Segment [Member]
Loans receivable	157,502	135,023
Residential Portfolio Segment [Member] | Classified [Member]
Loans receivable	1,665	4,093
Residential Portfolio Segment [Member] | Classified [Member] | Special Mention [Member]
Loans receivable	716	1,219
Residential Portfolio Segment [Member] | Classified [Member] | Substandard [Member]
Loans receivable	892	2,845
Residential Portfolio Segment [Member] | Classified [Member] | Doubtful [Member]
Loans receivable	57	29
Residential Portfolio Segment [Member] | Classified [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans receivable	0	0
Residential Portfolio Segment [Member] | Unclassified [Member]
Loans receivable	155,837	130,930
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	375,700	380,704
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Loans receivable	196,167	202,400
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans receivable	179,533	178,304
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Real Estate Loan [Member]
Loans receivable	10,188	11,548
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Commercial Real Estate Other [Member]
Loans receivable	17,202	18,524
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Special Mention [Member] | Real Estate Loan [Member]
Loans receivable	8,420	8,065
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Special Mention [Member] | Commercial Real Estate Other [Member]
Loans receivable	10,716	8,774
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Substandard [Member] | Real Estate Loan [Member]
Loans receivable	1,768	3,483
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Substandard [Member] | Commercial Real Estate Other [Member]
Loans receivable	6,486	9,750
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Doubtful [Member] | Real Estate Loan [Member]
Loans receivable	0	0
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Doubtful [Member] | Commercial Real Estate Other [Member]
Loans receivable	0	0
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Unlikely to be Collected Financing Receivable [Member] | Real Estate Loan [Member]
Loans receivable	0	0
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Real Estate Other [Member]
Loans receivable	0	0
Commercial Real Estate Portfolio Segment [Member] | Unclassified [Member] | Real Estate Loan [Member]
Loans receivable	185,979	190,852
Commercial Real Estate Portfolio Segment [Member] | Unclassified [Member] | Commercial Real Estate Other [Member]
Loans receivable	162,331	159,780
Consumer Portfolio Segment [Member]
Loans receivable	42,753	55,391
Consumer Portfolio Segment [Member] | Classified [Member]
Loans receivable	724	750
Consumer Portfolio Segment [Member] | Classified [Member] | Special Mention [Member]
Loans receivable	0	0
Consumer Portfolio Segment [Member] | Classified [Member] | Substandard [Member]
Loans receivable	616	600
Consumer Portfolio Segment [Member] | Classified [Member] | Doubtful [Member]
Loans receivable	55	132
Consumer Portfolio Segment [Member] | Classified [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans receivable	53	18
Consumer Portfolio Segment [Member] | Unclassified [Member]
Loans receivable	42,029	54,641
Commercial Portfolio Segment [Member]
Loans receivable	55,743	82,673
Commercial Portfolio Segment [Member] | Classified [Member]
Loans receivable	3,660	4,450
Commercial Portfolio Segment [Member] | Classified [Member] | Special Mention [Member]
Loans receivable	1,850	1,968
Commercial Portfolio Segment [Member] | Classified [Member] | Substandard [Member]
Loans receivable	1,810	2,482
Commercial Portfolio Segment [Member] | Classified [Member] | Doubtful [Member]
Loans receivable	0	0
Commercial Portfolio Segment [Member] | Classified [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans receivable	0	0
Commercial Portfolio Segment [Member] | Unclassified [Member]
Loans receivable	$ 52,083	$ 78,223