Note 4 - Loans Receivable and Related Allowance for Loan Losses - Activity in Allowance for Loan Losses by Portfolio (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
Beginning Balance	$ 9,685	$ 7,220	$ 9,580	$ 6,556
Charge-offs	(94)	(186)	(279)	(324)
Recoveries	7	25	22	35
Provision	250	1,100	525	1,892
Ending Balance	9,848	8,159	9,848	8,159
Individually evaluated for impairment	31		31		$ 60
Total	9,848	8,159	9,848	8,159	9,580
Individually evaluated for impairment	1,768		1,768		2,114
Loans and Leases Receivable, Net of Deferred Income, Total	804,139		804,139		809,918
Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0		0
Loans collectively evaluated for impairment	72,855		72,855		89,761
Financial Asset Originated [Member]
Loans collectively evaluated for impairment	9,817		9,817		9,520
Loans collectively evaluated for impairment	729,516		729,516		718,043
Residential Portfolio Segment [Member]
Beginning Balance	2,660	2,329	2,774	2,309
Charge-offs	0	0	0	(11)
Recoveries	0	0	0	0
Provision	(211)	253	(325)	284
Ending Balance	2,449	2,582	2,449	2,582
Individually evaluated for impairment	0		0		0
Total	2,449	2,582	2,449	2,582	2,774
Individually evaluated for impairment	312		312		329
Loans and Leases Receivable, Net of Deferred Income, Total	288,378		288,378		308,031
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	35,065		35,065		44,209
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	2,449		2,449		2,774
Loans collectively evaluated for impairment	253,001		253,001		263,493
Home Equity Loans and Lines of Credit [Member]
Beginning Balance	585	641	620	626
Charge-offs	0	0	0	(39)
Recoveries	1	11	8	11
Provision	(49)	2	(91)	56
Ending Balance	537	654	537	654
Individually evaluated for impairment	0		0		0
Total	537	654	537	654	620
Individually evaluated for impairment	4		4		3
Loans and Leases Receivable, Net of Deferred Income, Total	80,552		80,552		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		0
Loans collectively evaluated for impairment	7,245		7,245		8,491
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	537		537		620
Loans collectively evaluated for impairment	73,303		73,303		78,594
Commercial Real Estate Portfolio Segment [Member]
Beginning Balance	5,472	3,434	5,180	2,898
Charge-offs	(56)	0	(151)	(73)
Recoveries	1	2	1	5
Provision	409	465	796	1,071
Ending Balance	5,826	3,901	5,826	3,901
Individually evaluated for impairment	27		27		40
Total	5,826	3,901	5,826	3,901	5,180
Individually evaluated for impairment	1,328		1,328		1,639
Loans and Leases Receivable, Net of Deferred Income, Total	303,501		303,501		285,625
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	26,203		26,203		30,913
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	5,799		5,799		5,140
Loans collectively evaluated for impairment	275,970		275,970		253,073
Commercial Portfolio Segment [Member]
Beginning Balance	612	681	677	636
Charge-offs	0	(147)	0	(147)
Recoveries	0	1	1	1
Provision	63	268	(3)	313
Ending Balance	675	803	675	803
Individually evaluated for impairment	4		4		20
Total	675	803	675	803	677
Individually evaluated for impairment	124		124		143
Loans and Leases Receivable, Net of Deferred Income, Total	85,622		85,622		89,139
Commercial Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment	0		0		0
Loans collectively evaluated for impairment	3,598		3,598		5,131
Commercial Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	671		671		657
Loans collectively evaluated for impairment	81,900		81,900		83,865
Consumer Portfolio Segment [Member]
Beginning Balance	356	135	329	87
Charge-offs	(38)	(39)	(128)	(54)
Recoveries	5	11	12	18
Provision	38	112	148	168
Ending Balance	361	219	361	219
Individually evaluated for impairment	0		0		0
Total	361	$ 219	361	$ 219	329
Individually evaluated for impairment	0		0		0
Loans and Leases Receivable, Net of Deferred Income, Total	46,086		46,086		40,035
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	744		744		1,017
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment	361		361		329
Loans collectively evaluated for impairment	$ 45,342		$ 45,342		$ 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 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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