Note 3 - Loans Receivable and Related Allowance for Loan Losses - Analysis of Changes in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Balance at the beginning of the year	$ 9,580	$ 6,556
Provision for loan losses	1,066	3,247
Charge-offs	(369)	(473)
Recoveries	116	250
Balance at the end of the year	10,393	9,580
Individually evaluated for impairment	285	60
Total	10,393	9,580
Individually evaluated for impairment	1,886	2,114
Loans and Leases Receivable, Net of Deferred Income, Total	790,403	809,918
Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0	0
Loans collectively evaluated for impairment	60,007	89,761
Financial Asset Originated [Member]
Loans collectively evaluated for impairment	10,108	9,520
Loans collectively evaluated for impairment	728,510	718,043
Residential Portfolio Segment [Member]
Balance at the beginning of the year	2,774	2,309
Provision for loan losses	(439)	486
Charge-offs	0	(27)
Recoveries	0	6
Balance at the end of the year	2,335	2,774
Individually evaluated for impairment	1	0
Total	2,335	2,774
Individually evaluated for impairment	294	329
Loans and Leases Receivable, Net of Deferred Income, Total	273,823	308,031
Residential Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0	0
Loans collectively evaluated for impairment	29,573	44,209
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	2,334	2,774
Loans collectively evaluated for impairment	243,956	263,493
Home Equity Loans and Lines of Credit [Member]
Balance at the beginning of the year	620	626
Provision for loan losses	(81)	105
Charge-offs	(41)	(126)
Recoveries	27	15
Balance at the end of the year	525	620
Individually evaluated for impairment	0	0
Total	525	620
Individually evaluated for impairment	4	3
Loans and Leases Receivable, Net of Deferred Income, Total	75,810	87,088
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0	0
Loans collectively evaluated for impairment	6,370	8,491
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	525	620
Loans collectively evaluated for impairment	69,436	78,594
Commercial Real Estate Portfolio Segment [Member]
Balance at the beginning of the year	5,180	2,898
Provision for loan losses	1,186	2,250
Charge-offs	(150)	(75)
Recoveries	37	107
Balance at the end of the year	6,253	5,180
Individually evaluated for impairment	88	40
Total	6,253	5,180
Individually evaluated for impairment	1,225	1,639
Loans and Leases Receivable, Net of Deferred Income, Total	326,341	285,625
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0	0
Loans collectively evaluated for impairment	21,471	30,913
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	6,165	5,140
Loans collectively evaluated for impairment	303,645	253,073
Commercial Business [Member]
Balance at the beginning of the year	677	636
Provision for loan losses	208	134
Charge-offs	0	(163)
Recoveries	19	70
Balance at the end of the year	904	677
Individually evaluated for impairment	196	20
Total	904	677
Individually evaluated for impairment	363	143
Loans and Leases Receivable, Net of Deferred Income, Total	65,877	89,139
Commercial Business [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0	0
Loans collectively evaluated for impairment	2,055	5,131
Commercial Business [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	708	657
Loans collectively evaluated for impairment	63,459	83,865
Consumer Portfolio Segment [Member]
Balance at the beginning of the year	329	87
Provision for loan losses	192	272
Charge-offs	(178)	(82)
Recoveries	33	52
Balance at the end of the year	376	329
Individually evaluated for impairment	0	0
Total	376	329
Individually evaluated for impairment	0	0
Loans and Leases Receivable, Net of Deferred Income, Total	48,552	40,035
Consumer Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0	0
Loans collectively evaluated for impairment	538	1,017
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	376	329
Loans collectively evaluated for impairment	$ 48,014	$ 39,018

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 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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