Note 4 - Loans Receivable - Summary of Loans Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans receivable	$ 843,440		$ 780,538	$ 753,649
Deferred loan fees, net	(2,611)		(1,303)
Allowance for loan losses	(10,500)	$ (9,250)	(8,600)	(7,750)	$ (7,100)	$ (6,600)
Total loans, net	830,329		770,635
Residential Portfolio Segment [Member]
Loans receivable	150,818		157,898	145,148
Allowance for loan losses	(1,369)	(1,301)	(1,301)	(1,301)	(1,301)	(1,301)
Commercial Real Estate Portfolio Segment [Member]
Loans receivable	432,631		434,025	412,690
Allowance for loan losses	(6,096)	(5,214)	(4,826)	(4,276)	(3,923)	(3,593)
Home Equity Portfolio Segment [Member]
Loans receivable	58,755		56,414	55,582
Allowance for loan losses	(491)	(477)	(477)	(477)	(477)	(477)
Consumer Portfolio Segment [Member]
Loans receivable	20,231		18,882	19,181
Allowance for loan losses	(371)	(354)	(284)	(224)	(197)	(190)
Commercial Portfolio Segment [Member]
Loans receivable	181,005		113,319	121,048
Allowance for loan losses	$ (2,173)	$ (1,904)	$ (1,712)	$ (1,472)	$ (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 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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