Note 3 - Loans Receivable and Related Allowance for Loan Losses - Summary of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Loans and Leases Receivable, Net of Deferred Income, Total	$ 790,403	$ 809,918
Loans and Leases Receivable, Allowance, Ending Balance	10,393	9,580	$ 6,556
Total loans, net	780,010	800,338
Mortgage Receivable [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	675,974	680,744
Other Loans [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	114,429	129,174
Residential Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	273,823	308,031
Loans and Leases Receivable, Allowance, Ending Balance	2,335	2,774	2,309
Residential Portfolio Segment [Member] \| Mortgage Receivable [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	273,823	308,031
Home Equity Loans and Lines of Credit [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	75,810	87,088
Loans and Leases Receivable, Allowance, Ending Balance	525	620	626
Home Equity Loans and Lines of Credit [Member] \| Mortgage Receivable [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	75,810	87,088
Commercial Real Estate Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	326,341	285,625
Loans and Leases Receivable, Allowance, Ending Balance	6,253	5,180	2,898
Commercial Real Estate Portfolio Segment [Member] \| Mortgage Receivable [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	326,341	285,625
Commercial Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	65,877	89,139
Commercial Portfolio Segment [Member] \| Other Loans [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	65,877	89,139
Consumer Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	48,552	40,035
Loans and Leases Receivable, Allowance, Ending Balance	376	329	$ 87
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	$ 48,552	$ 40,035

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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