Note 5 - Loans Disaggregated by Impairment Method (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	$ 11,184	$ 10,826	$ 9,887	$ 8,834
Allowance for loan losses - individually evaluated for impairment	2,873	3,050
Allowance for loan losses - collectively evaluated for impairment	7,806	7,226
Loans and leases receivable	927,147	921,856
Loans - individually evaluated for impairment	12,192	14,516
Loans - collectively evaluated for impairment	914,955	907,340
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	3,368	4,050	4,689	3,092
Allowance for loan losses - individually evaluated for impairment	2,090	2,421
Allowance for loan losses - collectively evaluated for impairment	1,278	1,629
Loans and leases receivable	148,610	227,431
Loans - individually evaluated for impairment	3,517	4,503
Loans - collectively evaluated for impairment	145,093	222,928
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	363	346	590	551
Allowance for loan losses - individually evaluated for impairment	0	0
Allowance for loan losses - collectively evaluated for impairment	363	346
Loans and leases receivable	55,855	57,594
Loans - collectively evaluated for impairment	55,855	57,594
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	4,280	3,736	2,519	2,824
Allowance for loan losses - individually evaluated for impairment	312	432
Allowance for loan losses - collectively evaluated for impairment	3,968	3,304
Loans and leases receivable	451,404	377,586
Loans - individually evaluated for impairment	5,654	6,323
Loans - collectively evaluated for impairment	445,750	371,263
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	1,035	871	629	754
Allowance for loan losses - individually evaluated for impairment	368	73
Allowance for loan losses - collectively evaluated for impairment	667	798
Loans and leases receivable	84,741	81,897
Loans - individually evaluated for impairment	1,387	2,051
Loans - collectively evaluated for impairment	83,354	79,846
State and Political Subdivisions Portfolio Segment [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	69	89	115	153
Allowance for loan losses - individually evaluated for impairment	0	0
Allowance for loan losses - collectively evaluated for impairment	69	89
Loans and leases receivable	19,775	25,302
Loans - individually evaluated for impairment	0	0
Loans - collectively evaluated for impairment	19,775	25,302
Retail Portfolio Segment [Member] \| Consumer Loans [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	542	265	230	164
Allowance for loan losses - individually evaluated for impairment	3	7
Allowance for loan losses - collectively evaluated for impairment	539	258
Loans and leases receivable	4,699	5,364
Loans - individually evaluated for impairment	53	61
Loans - collectively evaluated for impairment	4,646	5,303
Retail Portfolio Segment [Member] \| Family Residential Mortgages [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	646	533	549	497
Allowance for loan losses - collectively evaluated for impairment	646	533
Loans and leases receivable	100,281	82,739
Loans - individually evaluated for impairment	893	813
Loans - collectively evaluated for impairment	99,388	81,926
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	376	386	310	338
Allowance for loan losses - individually evaluated for impairment	100	117
Allowance for loan losses - collectively evaluated for impairment	276	269
Loans and leases receivable	61,782	63,943
Loans - individually evaluated for impairment	688	765
Loans - collectively evaluated for impairment	61,094	63,178
Unallocated Financing Receivables [Member]
Credit Losses Related To Financing Receivables Current And Noncurrent [Line Items]
Allowance for loan losses	$ 505	$ 550	$ 256	$ 461

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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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