Note 5 - Loans Disaggregated by Impairment Method (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	$ 10,531	$ 11,184	$ 10,826	$ 9,887
Allowance for loan losses - individually evaluated for impairment	696	2,873
Allowance for loan losses - collectively evaluated for impairment	9,333	7,806
Loans and leases receivable	1,039,637	927,147
Loans - individually evaluated for impairment	9,567	12,192
Loans - collectively evaluated for impairment	1,030,070	914,955
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	1,316	3,368	4,050	4,689
Allowance for loan losses - individually evaluated for impairment	125	2,090
Allowance for loan losses - collectively evaluated for impairment	1,191	1,278
Loans and leases receivable	160,875	148,610
Loans - individually evaluated for impairment	1,821	3,517
Loans - collectively evaluated for impairment	159,054	145,093
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	755	363	346	590
Allowance for loan losses - individually evaluated for impairment	0	0
Allowance for loan losses - collectively evaluated for impairment	755	363
Loans and leases receivable	62,955	55,855
Loans - collectively evaluated for impairment	62,955	55,855
Commercial Portfolio Segment [Member] \| Secured by Commercial Real Estate [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	5,002	4,280	3,736	2,519
Allowance for loan losses - individually evaluated for impairment	131	312
Allowance for loan losses - collectively evaluated for impairment	4,871	3,968
Loans and leases receivable	518,070	451,404
Loans - individually evaluated for impairment	5,309	5,654
Loans - collectively evaluated for impairment	512,761	445,750
Commercial Portfolio Segment [Member] \| Secured by Residential Real Estate [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	1,240	1,035	871	629
Allowance for loan losses - individually evaluated for impairment	321	368
Allowance for loan losses - collectively evaluated for impairment	919	667
Loans and leases receivable	103,419	84,741
Loans - individually evaluated for impairment	1,362	1,387
Loans - collectively evaluated for impairment	102,057	83,354
State and Political Subdivisions Portfolio Segment [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	94	69	89	115
Allowance for loan losses - individually evaluated for impairment	0	0
Allowance for loan losses - collectively evaluated for impairment	94	69
Loans and leases receivable	20,971	19,775
Loans - individually evaluated for impairment	0	0
Loans - collectively evaluated for impairment	20,971	19,775
Retail Portfolio Segment [Member] \| Consumer Loans [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	502	542	265	230
Allowance for loan losses - individually evaluated for impairment	0	3
Allowance for loan losses - collectively evaluated for impairment	502	539
Loans and leases receivable	4,113	4,699
Loans - individually evaluated for impairment	45	53
Loans - collectively evaluated for impairment	4,068	4,646
Retail Portfolio Segment [Member] \| Family Residential Mortgages [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	683	646	533	549
Allowance for loan losses - collectively evaluated for impairment	683	646
Loans and leases receivable	105,654	100,281
Loans - individually evaluated for impairment	628	893
Loans - collectively evaluated for impairment	105,026	99,388
Retail Portfolio Segment [Member] \| Home Equity Loans and Lines [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	437	376	386	310
Allowance for loan losses - individually evaluated for impairment	119	100
Allowance for loan losses - collectively evaluated for impairment	318	276
Loans and leases receivable	63,580	61,782
Loans - individually evaluated for impairment	402	688
Loans - collectively evaluated for impairment	63,178	61,094
Unallocated Financing Receivables [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	$ 502	$ 505	$ 550	$ 256

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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