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
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Beginning Balance	$ 10,393	$ 9,580
Charge-offs	(98)	(184)
Recoveries	53	14
Provision	(80)	275
Ending Balance	10,268	9,685
Individually evaluated for impairment	128		$ 285
Total	10,268	9,685	10,393
Individually evaluated for impairment	2,981		1,886
Loans and Leases Receivable, Net of Deferred Income	805,200		790,403
Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0
Loans collectively evaluated for impairment	56,067		60,007
Financial Asset Originated [Member]
Loans collectively evaluated for impairment	10,140		10,108
Loans collectively evaluated for impairment	746,152		728,510
Residential Portfolio Segment [Member]
Beginning Balance	2,335	2,774
Charge-offs	0	0
Recoveries	0	0
Provision	(25)	(114)
Ending Balance	2,310	2,660
Individually evaluated for impairment	7		1
Total	2,310	2,660	2,335
Individually evaluated for impairment	287		294
Loans and Leases Receivable, Net of Deferred Income	273,724		273,823
Residential Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0
Loans collectively evaluated for impairment	27,156		29,573
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	2,303		2,334
Loans collectively evaluated for impairment	246,281		243,956
Home Equity Loans and Lines of Credit [Member]
Beginning Balance	525	620
Charge-offs	(15)	0
Recoveries	0	8
Provision	(25)	(43)
Ending Balance	485	585
Individually evaluated for impairment	0		0
Total	485	585	525
Individually evaluated for impairment	4		4
Loans and Leases Receivable, Net of Deferred Income	73,731		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
Loans collectively evaluated for impairment	6,203		6,370
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	485		525
Loans collectively evaluated for impairment	67,524		69,436
Commercial Real Estate Portfolio Segment [Member]
Beginning Balance	6,253	5,180
Charge-offs	0	(94)
Recoveries	47	0
Provision	144	386
Ending Balance	6,444	5,472
Individually evaluated for impairment	118		88
Total	6,444	5,472	6,253
Individually evaluated for impairment	2,601		1,225
Loans and Leases Receivable, Net of Deferred Income	347,447		326,341
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	20,108		21,471
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	6,326		6,165
Loans collectively evaluated for impairment	324,738		303,645
Commercial Business [Member]
Beginning Balance	904	677
Charge-offs	0	0
Recoveries	0	0
Provision	(253)	(65)
Ending Balance	651	612
Individually evaluated for impairment	3		196
Total	651	612	904
Individually evaluated for impairment	89		363
Loans and Leases Receivable, Net of Deferred Income	61,381		65,877
Commercial Business [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0
Loans collectively evaluated for impairment	2,077		2,055
Commercial Business [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	648		708
Loans collectively evaluated for impairment	59,215		63,459
Consumer Portfolio Segment [Member]
Beginning Balance	376	329
Charge-offs	(83)	(90)
Recoveries	6	6
Provision	79	111
Ending Balance	378	356
Individually evaluated for impairment	0		0
Total	378	$ 356	376
Individually evaluated for impairment	0		0
Loans and Leases Receivable, Net of Deferred Income	48,917		48,552
Consumer Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0
Loans collectively evaluated for impairment	523		538
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	378		376
Loans collectively evaluated for impairment	$ 48,394		$ 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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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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