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	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Beginning Balance	$ 10,525	$ 9,848	$ 10,393	$ 9,580
Charge-offs	(93)	(69)	(368)	(347)
Recoveries	17	45	129	66
Provision	140	125	435	650
Ending Balance	10,589	9,949	10,589	9,949
Individually evaluated for impairment	191		191		$ 285
Total	10,589	9,949	10,589	9,949	10,393
Individually evaluated for impairment	2,562		2,562		1,886
Loans and Leases Receivable, Net of Deferred Income	810,106		810,106		790,403
Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0		0
Loans collectively evaluated for impairment	48,205		48,205		60,007
Financial Asset Originated [Member]
Loans collectively evaluated for impairment	10,398		10,398		10,108
Loans collectively evaluated for impairment	759,339		759,339		728,510
Residential Portfolio Segment [Member]
Beginning Balance	2,505	2,449	2,335	2,774
Charge-offs	(18)	0	(36)	0
Recoveries	0	0	0	0
Provision	49	(101)	237	(426)
Ending Balance	2,536	2,348	2,536	2,348
Individually evaluated for impairment	17		17		1
Total	2,536	2,348	2,536	2,348	2,335
Individually evaluated for impairment	270		270		294
Loans and Leases Receivable, Net of Deferred Income	294,286		294,286		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	23,500		23,500		29,573
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	2,519		2,519		2,334
Loans collectively evaluated for impairment	270,516		270,516		243,956
Home Equity Loans and Lines of Credit [Member]
Beginning Balance	493	537	525	620
Charge-offs	(49)	(36)	(63)	(36)
Recoveries	3	11	43	19
Provision	48	21	(10)	(70)
Ending Balance	495	533	495	533
Individually evaluated for impairment	0		0		0
Total	495	533	495	533	525
Individually evaluated for impairment	4		4		4
Loans and Leases Receivable, Net of Deferred Income	72,699		72,699		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	5,278		5,278		6,370
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	495		495		525
Loans collectively evaluated for impairment	67,417		67,417		69,436
Commercial Real Estate Portfolio Segment [Member]
Beginning Balance	6,542	5,826	6,253	5,180
Charge-offs	(7)	0	(7)	(151)
Recoveries	5	21	63	22
Provision	77	153	308	949
Ending Balance	6,617	6,000	6,617	6,000
Individually evaluated for impairment	157		157		88
Total	6,617	6,000	6,617	6,000	6,253
Individually evaluated for impairment	2,193		2,193		1,225
Loans and Leases Receivable, Net of Deferred Income	344,716		344,716		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	17,325		17,325		21,471
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	6,460		6,460		6,165
Loans collectively evaluated for impairment	325,198		325,198		303,645
Commercial Business [Member]
Beginning Balance	622	675	904	677
Charge-offs	0	0	0	0
Recoveries	0	1	0	1
Provision	(27)	7	(309)	5
Ending Balance	595	683	595	683
Individually evaluated for impairment	17		17		196
Total	595	683	595	683	904
Individually evaluated for impairment	95		95		363
Loans and Leases Receivable, Net of Deferred Income	56,026		56,026		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	1,759		1,759		2,055
Commercial Business [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	578		578		708
Loans collectively evaluated for impairment	54,172		54,172		63,459
Consumer Portfolio Segment [Member]
Beginning Balance	363	361	376	329
Charge-offs	(19)	(33)	(262)	(160)
Recoveries	9	12	23	24
Provision	(7)	45	209	192
Ending Balance	346	385	346	385
Individually evaluated for impairment	0		0		0
Total	346	$ 385	346	$ 385	376
Individually evaluated for impairment	0		0		0
Loans and Leases Receivable, Net of Deferred Income	42,379		42,379		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	343		343		538
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	346		346		376
Loans collectively evaluated for impairment	$ 42,036		$ 42,036		$ 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 of expense related to estimated loss from loan and lease transactions.

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