Note 4 - Loans Receivable - Summary of Loans Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans receivable	$ 823,219	$ 780,538	$ 729,103
Deferred loan fees, net	(1,185)	(1,303)
Allowance for loan losses	(9,250)	(8,600)	(7,100)	$ (6,600)
Total loans, net	812,784	770,635
Residential Portfolio Segment [Member]
Loans receivable	160,047	157,898	144,313
Allowance for loan losses	(1,301)	(1,301)	(1,301)	(1,301)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	455,620	434,025	394,988
Allowance for loan losses	(5,214)	(4,826)	(3,923)	(3,593)
Home Equity Portfolio Segment [Member]
Loans receivable	57,752	56,414	54,637
Allowance for loan losses	(477)	(477)	(477)	(477)
Consumer Portfolio Segment [Member]
Loans receivable	19,924	18,882	19,043
Allowance for loan losses	(354)	(284)	(197)	(190)
Commercial Portfolio Segment [Member]
Loans receivable	129,876	113,319	116,122
Allowance for loan losses	$ (1,904)	$ (1,712)	$ (1,202)	$ (1,039)

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 deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and 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 and loans held for sale.

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