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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Note 4 - Loans Receivable and Related Allowance for Loan Losses - Summary of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Loans, gross	$ 840,291		$ 701,904
Loans and Leases Receivable, Allowance, Ending Balance	8,905	$ 8,159	6,556	$ 6,509	$ 6,580	$ 6,508
Total loans, net	831,386		695,348
Mortgage Receivable [Member]
Loans, gross	682,036		620,662
Other Loans [Member]
Loans, gross	158,255		81,242
Residential Portfolio Segment [Member]
Loans, gross	305,824		293,170
Loans and Leases Receivable, Allowance, Ending Balance	2,698	2,582	2,309	2,241	2,225	2,198
Residential Portfolio Segment [Member] \| Mortgage Receivable [Member]
Loans, gross	305,824		293,170
Home Equity Loans and Lines of Credit [Member]
Loans, gross	90,764		97,541
Loans and Leases Receivable, Allowance, Ending Balance	661	654	626	635	642	648
Home Equity Loans and Lines of Credit [Member] \| Mortgage Receivable [Member]
Loans, gross	90,764		97,541
Commercial Real Estate Portfolio Segment [Member]
Loans, gross	285,448		229,951
Loans and Leases Receivable, Allowance, Ending Balance	4,479	3,901	2,898	2,954	3,043	3,106
Commercial Real Estate Portfolio Segment [Member] \| Mortgage Receivable [Member]
Loans, gross	285,448		229,951
Commercial Portfolio Segment [Member]
Loans, gross	120,535		66,603
Loans and Leases Receivable, Allowance, Ending Balance	758	803	636	620	615	500
Commercial Portfolio Segment [Member] \| Other Loans [Member]
Loans, gross	120,535		66,603
Consumer Portfolio Segment [Member]
Loans, gross	37,720		14,639
Loans and Leases Receivable, Allowance, Ending Balance	309	$ 219	87	$ 59	$ 55	$ 56
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Loans, gross	$ 37,720		$ 14,639