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
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Dec. 31, 2019
Beginning Balance	$ 6,556	$ 6,508
Charge-offs	(138)	(129)
Recoveries	10	80
Provision	792	180
Ending Balance	7,220	6,639
Individually evaluated for impairment			$ 26	$ 5
Total	6,556	6,639	7,220	6,556
Individually evaluated for impairment			1,658	483
Loans, gross			741,950	701,904
Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			115,320	123,329
Financial Asset Originated [Member]
Loans collectively evaluated for impairment			7,194	6,551
Loans collectively evaluated for impairment			624,972	578,092
Residential Portfolio Segment [Member]
Beginning Balance	2,309	2,198
Charge-offs	(11)	(10)
Recoveries		40
Provision	31	28
Ending Balance	2,329	2,256
Individually evaluated for impairment			2	5
Total	2,329	2,256	2,329	2,309
Individually evaluated for impairment			349	358
Loans, gross			294,361	293,170
Residential Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			57,891	60,523
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			2,327	2,304
Loans collectively evaluated for impairment			236,121	232,289
Home Equity Loans and Lines of Credit [Member]
Beginning Balance	626	648
Charge-offs	(39)	(4)
Recoveries		1
Provision	54	5
Ending Balance	641	650
Individually evaluated for impairment
Total	641	650	641	626
Individually evaluated for impairment			4	4
Loans, gross			95,459	97,541
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			10,177	10,901
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			641	626
Loans collectively evaluated for impairment			85,278	86,636
Commercial Real Estate Portfolio Segment [Member]
Beginning Balance	2,898	3,106
Charge-offs	(73)	(5)
Recoveries	3	15
Provision	606	(73)
Ending Balance	3,434	3,043
Individually evaluated for impairment			19
Total	3,434	3,043	3,434	2,898
Individually evaluated for impairment			1,217	81
Loans, gross			263,948	229,951
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			38,619	41,993
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			3,415	2,898
Loans collectively evaluated for impairment			224,112	187,877
Commercial Portfolio Segment [Member]
Beginning Balance	636	500
Charge-offs		(71)
Recoveries
Provision	45	206
Ending Balance	681	635
Individually evaluated for impairment			5
Total	681	635	681	636
Individually evaluated for impairment			88	40
Loans, gross			69,077	66,603
Commercial Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			7,026	7,930
Commercial Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			676	636
Loans collectively evaluated for impairment			61,963	58,633
Consumer Portfolio Segment [Member]
Beginning Balance	87	56
Charge-offs	(15)	(39)
Recoveries	7	24
Provision	56	14
Ending Balance	135	55
Individually evaluated for impairment
Total	$ 135	$ 55	135	87
Individually evaluated for impairment
Loans, gross			19,105	14,639
Consumer Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			1,607	1,982
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			135	87
Loans collectively evaluated for impairment			$ 17,498	$ 12,657

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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The balance of financing receivables 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 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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