Note 4 - Loans Receivable - Allowance for Loan Losses Activity (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Allowance for loan losses, beginning balance	$ 11,900	$ 9,250	$ 11,600	$ 8,600
Charge-offs	(33)	(11)	(51)	(47)
Recoveries	11	34	30	50
Provision	22	1,227	321	1,897
Allowance for loan losses, ending balance	11,900	10,500	11,900	10,500
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment	206	167	206	167
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	11,694	10,333	11,694	10,333
Loans receivable	876,599	843,440	876,599	843,440	$ 843,141
Loans receivable, ending balance, loans individually evaluated for impairment	7,270	7,861	7,270	7,861
Loans receivable, ending balance, loans collectively evaluated for impairment	869,329	835,579	869,329	835,579
Residential Portfolio Segment [Member]
Allowance for loan losses, beginning balance	1,542	1,301	1,506	1,301
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	2	68	38	68
Allowance for loan losses, ending balance	1,544	1,369	1,544	1,369
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment	199	97	199	97
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	1,345	1,272	1,345	1,272
Loans receivable	141,621	150,818	141,621	150,818	157,092
Loans receivable, ending balance, loans individually evaluated for impairment	981	1,266	981	1,266
Loans receivable, ending balance, loans collectively evaluated for impairment	140,640	149,552	140,640	149,552
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance	7,131	5,214	6,951	4,826
Charge-offs	(25)	0	(35)	(18)
Recoveries	7	2	9	8
Provision	14	880	202	1,280
Allowance for loan losses, ending balance	7,127	6,096	7,127	6,096
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment	0	0	0	0
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	7,127	6,096	7,127	6,096
Loans receivable	497,898	432,631	497,898	432,631	447,867
Loans receivable, ending balance, loans individually evaluated for impairment	4,387	3,922	4,387	3,922
Loans receivable, ending balance, loans collectively evaluated for impairment	493,511	428,709	493,511	428,709
Home Equity Portfolio Segment [Member]
Allowance for loan losses, beginning balance	521	477	515	477
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	1	14	7	14
Allowance for loan losses, ending balance	522	491	522	491
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment	0	0	0	0
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	522	491	522	491
Loans receivable	55,739	58,755	55,739	58,755	56,563
Loans receivable, ending balance, loans individually evaluated for impairment	131	191	131	191
Loans receivable, ending balance, loans collectively evaluated for impairment	55,608	58,564	55,608	58,564
Consumer Portfolio Segment [Member]
Allowance for loan losses, beginning balance	369	354	364	284
Charge-offs	(8)	(3)	(10)	(11)
Recoveries	2	3	6	11
Provision	0	17	3	87
Allowance for loan losses, ending balance	363	371	363	371
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment	0	0	0	0
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	363	371	363	371
Loans receivable	18,859	20,231	18,859	20,231	20,168
Loans receivable, ending balance, loans individually evaluated for impairment	79	198	79	198
Loans receivable, ending balance, loans collectively evaluated for impairment	18,780	20,033	18,780	20,033
Commercial Portfolio Segment [Member]
Allowance for loan losses, beginning balance	2,337	1,904	2,264	1,712
Charge-offs	0	(8)	(6)	(18)
Recoveries	2	29	15	31
Provision	5	248	71	448
Allowance for loan losses, ending balance	2,344	2,173	2,344	2,173
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment	7	70	7	70
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	2,337	2,103	2,337	2,103
Loans receivable	162,482	181,005	162,482	181,005	$ 161,451
Loans receivable, ending balance, loans individually evaluated for impairment	1,692	2,284	1,692	2,284
Loans receivable, ending balance, loans collectively evaluated for impairment	$ 160,790	$ 178,721	$ 160,790	$ 178,721

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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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 of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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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Amount of credit loss expense (reversal of expense) for financing receivable.

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