Note 6 - Allowance for Credit Losses and Credit Quality Information - Aging of Past Due Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Loans receivable	$ 858,108	$ 787,887
Loans 90 days or more past due and still accruing	0	0
Loans 90 days or more past due and still accruing	0	0
Residential Portfolio Segment [Member]
Loans receivable	264,303	205,890
Loans 90 days or more past due and still accruing	0	0
Loans 90 days or more past due and still accruing	0	0
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	489,953	471,345
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Loans receivable	271,531	249,783
Loans 90 days or more past due and still accruing	0	0
Loans 90 days or more past due and still accruing	0	0
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans receivable	218,422	221,562
Loans 90 days or more past due and still accruing	0	0
Loans 90 days or more past due and still accruing	0	0
Consumer Portfolio Segment [Member]
Loans receivable	42,734	44,817
Loans 90 days or more past due and still accruing	0	0
Loans 90 days or more past due and still accruing	0	0
Commercial Portfolio Segment [Member]
Loans receivable	61,118	65,835
Loans 90 days or more past due and still accruing	0	0
Loans 90 days or more past due and still accruing	0	0
Financial Asset, 30 to 59 Days Past Due [Member]
Loans receivable	814	1,352
Financial Asset, 30 to 59 Days Past Due [Member] | Residential Portfolio Segment [Member]
Loans receivable	453	380
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Loans receivable	0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans receivable	0	578
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Portfolio Segment [Member]
Loans receivable	361	394
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Loans receivable	0	0
Financial Asset, 60 to 89 Days Past Due [Member]
Loans receivable	472	268
Financial Asset, 60 to 89 Days Past Due [Member] | Residential Portfolio Segment [Member]
Loans receivable	71	145
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Loans receivable	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans receivable	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Portfolio Segment [Member]
Loans receivable	92	123
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Loans receivable	309	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Loans receivable	1,631	569
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential Portfolio Segment [Member]
Loans receivable	363	481
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Loans receivable	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans receivable	399	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Portfolio Segment [Member]
Loans receivable	57	88
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Loans receivable	812	0
Financial Asset, Past Due [Member]
Loans receivable	2,917	2,189
Financial Asset, Past Due [Member] | Residential Portfolio Segment [Member]
Loans receivable	887	1,006
Financial Asset, Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Loans receivable	0	0
Financial Asset, Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans receivable	399	578
Financial Asset, Past Due [Member] | Consumer Portfolio Segment [Member]
Loans receivable	510	605
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member]
Loans receivable	1,121	0
Financial Asset, Not Past Due [Member]
Loans receivable	855,191	785,698
Financial Asset, Not Past Due [Member] | Residential Portfolio Segment [Member]
Loans receivable	263,416	204,884
Financial Asset, Not Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Loans receivable	271,531	249,783
Financial Asset, Not Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans receivable	218,023	220,984
Financial Asset, Not Past Due [Member] | Consumer Portfolio Segment [Member]
Loans receivable	42,224	44,212
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member]
Loans receivable	$ 59,997	$ 65,835