Note 4 - Loans Receivable and Related Allowance for Loan Losses - Analysis of Changes in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Mar. 31, 2022	Dec. 31, 2021
Beginning Balance	$ 10,268	$ 9,685	$ 10,393	$ 9,580
Charge-offs	(177)	(94)	(275)	(279)
Recoveries	59	7	112	22
Provision	375	250	295	525
Ending Balance	10,525	9,848	10,525	9,848
Individually evaluated for impairment	194		194			$ 285
Total	10,525	9,848	10,525	9,848	$ 10,268	10,393
Individually evaluated for impairment	2,644		2,644			1,886
Loans and Leases Receivable, Net of Deferred Income	810,676		810,676		810,676	790,403
Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0			0
Loans collectively evaluated for impairment	51,175		51,175			60,007
Financial Asset Originated [Member]
Loans collectively evaluated for impairment	10,331		10,331			10,108
Loans collectively evaluated for impairment	756,857		756,857			728,510
Residential Portfolio Segment [Member]
Beginning Balance	2,310	2,660	2,335	2,774
Charge-offs	(17)	0	(17)	0
Recoveries	0	0	0	0
Provision	212	(211)	187	(325)
Ending Balance	2,505	2,449	2,505	2,449
Individually evaluated for impairment	15		15			1
Total	2,505	2,449	2,505	2,449	2,310	2,335
Individually evaluated for impairment	279		279			294
Loans and Leases Receivable, Net of Deferred Income	291,779		291,779		291,779	273,823
Residential Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0			0
Loans collectively evaluated for impairment	24,865		24,865			29,573
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	2,490		2,490			2,334
Loans collectively evaluated for impairment	266,635		266,635			243,956
Home Equity Loans and Lines of Credit [Member]
Beginning Balance	485	585	525	620
Charge-offs	0	0	(15)	0
Recoveries	40	1	40	8
Provision	(32)	(49)	(57)	(91)
Ending Balance	493	537	493	537
Individually evaluated for impairment	0		0			0
Total	493	537	493	537	485	525
Individually evaluated for impairment	4		4			4
Loans and Leases Receivable, Net of Deferred Income	73,625		73,625		73,625	75,810
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0			0
Loans collectively evaluated for impairment	5,666		5,666			6,370
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	493		493			525
Loans collectively evaluated for impairment	67,955		67,955			69,436
Commercial Real Estate Portfolio Segment [Member]
Beginning Balance	6,444	5,472	6,253	5,180
Charge-offs	0	(56)	0	(151)
Recoveries	11	1	58	1
Provision	87	409	231	796
Ending Balance	6,542	5,826	6,542	5,826
Individually evaluated for impairment	177		177			88
Total	6,542	5,826	6,542	5,826	6,444	6,253
Individually evaluated for impairment	2,277		2,277			1,225
Loans and Leases Receivable, Net of Deferred Income	342,041		342,041		342,041	326,341
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0			0
Loans collectively evaluated for impairment	18,501		18,501			21,471
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	6,365		6,365			6,165
Loans collectively evaluated for impairment	321,263		321,263			303,645
Commercial Business [Member]
Beginning Balance	651	612	904	677
Charge-offs	0	0	0	0
Recoveries	0	0	0	1
Provision	(29)	63	(282)	(3)
Ending Balance	622	675	622	675
Individually evaluated for impairment	2		2			196
Total	622	675	622	675	651	904
Individually evaluated for impairment	84		84			363
Loans and Leases Receivable, Net of Deferred Income	57,819		57,819			65,877
Commercial Business [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0			0
Loans collectively evaluated for impairment	1,748		1,748			2,055
Commercial Business [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	620		620			708
Loans collectively evaluated for impairment	55,987		55,987			63,459
Consumer Portfolio Segment [Member]
Beginning Balance	378	356	376	329
Charge-offs	(160)	(38)	(243)	(128)
Recoveries	8	5	14	12
Provision	137	38	216	148
Ending Balance	363	361	363	361
Individually evaluated for impairment	0		0			0
Total	363	$ 361	363	$ 361	378	376
Individually evaluated for impairment	0		0			0
Loans and Leases Receivable, Net of Deferred Income	45,412		45,412		$ 45,412	48,552
Consumer Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0			0
Loans collectively evaluated for impairment	395		395			538
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	363		363			376
Loans collectively evaluated for impairment	$ 45,017		$ 45,017			$ 48,014

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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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 and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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