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, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Loans, gross	$ 694,866		$ 715,172
Loans and Leases Receivable, Allowance, Ending Balance	6,509	$ 6,580	6,508	$ 6,360	$ 6,118	$ 6,127
Total loans, net	688,357		708,664
Mortgage Receivable [Member]
Loans, gross	613,634		637,891
Other Loans [Member]
Loans, gross	81,232		77,281
Residential Portfolio Segment [Member]
Loans, gross	287,437		295,405
Loans and Leases Receivable, Allowance, Ending Balance	2,241	2,225	2,198	2,161	2,033	2,090
Residential Portfolio Segment [Member] \| Mortgage Receivable [Member]
Loans, gross	287,437		295,405
Home Equity Loans and Lines of Credit [Member]
Loans, gross	98,628		103,752
Loans and Leases Receivable, Allowance, Ending Balance	635	642	648	659	650	646
Home Equity Loans and Lines of Credit [Member] \| Mortgage Receivable [Member]
Loans, gross	98,628		103,752
Commercial Real Estate Portfolio Segment [Member]
Loans, gross	227,569		238,734
Loans and Leases Receivable, Allowance, Ending Balance	2,954	3,043	3,106	2,970	2,882	2,753
Commercial Real Estate Portfolio Segment [Member] \| Mortgage Receivable [Member]
Loans, gross	227,569		238,734
Commercial Portfolio Segment [Member]
Loans, gross	69,834		66,009
Loans and Leases Receivable, Allowance, Ending Balance	620	615	500	510	499	585
Commercial Portfolio Segment [Member] \| Other Loans [Member]
Loans, gross	69,834		66,009
Consumer Portfolio Segment [Member]
Loans, gross	11,398		11,272
Loans and Leases Receivable, Allowance, Ending Balance	59	$ 55	56	$ 60	$ 54	$ 53
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Loans, gross	$ 11,398		$ 11,272