Note 9 - Allowance for Credit Losses and Credit Quality Information - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Balance	$ 11,824	$ 10,277	$ 10,277
Provision for losses	(208)	(32)
Charge-offs	(30)		(334)
Recoveries	0	27
Balance	11,586	11,342	11,824
Individual reserves	419		428
Collective reserves	11,167		11,396
Balance	11,586	11,342	11,824
Individually reviewed for impairment	3,260		4,284
Collectively reviewed for impairment	865,470		853,824
Ending balance	868,730		858,108
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		1,070	1,070
Balance
Residential Portfolio Segment [Member]
Balance	1,426	1,261	1,261
Provision for losses	(181)	(44)
Charge-offs	(30)
Recoveries	0	1
Balance	1,215	959	1,426
Individual reserves	26		28
Collective reserves	1,189		1,398
Balance	1,215	959	1,426
Individually reviewed for impairment	958		979
Collectively reviewed for impairment	259,644		263,324
Ending balance	260,602		264,303
Residential Portfolio Segment [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		(259)	(259)
Balance
Commercial Real Estate Portfolio Segment [Member]
Balance	7,514	7,026	7,026
Provision for losses	(94)	23
Charge-offs	0
Recoveries	0	0
Balance	7,420	7,561	7,514
Individual reserves	0		0
Collective reserves	7,420		7,514
Balance	7,420	7,561	7,514
Individually reviewed for impairment	636		668
Collectively reviewed for impairment	502,703		489,285
Ending balance	503,339		489,953
Commercial Real Estate Portfolio Segment [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		512	512
Balance
Consumer Portfolio Segment [Member]
Balance	607	1,058	1,058
Provision for losses	(111)	46
Charge-offs	0		(50)
Recoveries	0	1
Balance	496	620	607
Individual reserves	97		103
Collective reserves	399		504
Balance	496	620	607
Individually reviewed for impairment	382		425
Collectively reviewed for impairment	40,728		42,309
Ending balance	41,110		42,734
Consumer Portfolio Segment [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		(485)	(485)
Balance
Commercial Portfolio Segment [Member]
Balance	2,277	932	932
Provision for losses	178	(57)
Charge-offs	0
Recoveries	0	25
Balance	2,455	2,202	2,277
Individual reserves	296		297
Collective reserves	2,159		1,980
Balance	2,455	2,202	2,277
Individually reviewed for impairment	1,284		2,212
Collectively reviewed for impairment	62,395		58,906
Ending balance	$ 63,679		61,118
Commercial Portfolio Segment [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Balance		$ 1,302	$ 1,302
Balance