Note 3 - Loans and Allowance for Loan Losses - Recorded Investment in Nonperforming Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Loans and Leases Receivable, Net of Deferred Income, Total	$ 520,979	$ 525,818
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	129,619	131,217
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	18,322	17,328
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	132,379	135,114
Commercial Portfolio Segment [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	68,208	82,274
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	49,817	52,001
Nonperforming Financial Instruments [Member]
Nonaccrual Loans	1,726	1,406
Loans 90+ Days Past Due Still Accruing	52	59
Loans and Leases Receivable, Net of Deferred Income, Total	1,778	1,465
Nonperforming Financial Instruments [Member] | Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Nonaccrual Loans	1,092	1,154
Loans 90+ Days Past Due Still Accruing	52	0
Loans and Leases Receivable, Net of Deferred Income, Total	1,144	1,154
Nonperforming Financial Instruments [Member] | Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member]
Nonaccrual Loans	151	97
Loans 90+ Days Past Due Still Accruing	0	59
Loans and Leases Receivable, Net of Deferred Income, Total	151	156
Nonperforming Financial Instruments [Member] | Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member]
Nonaccrual Loans	0	0
Loans 90+ Days Past Due Still Accruing	0	0
Loans and Leases Receivable, Net of Deferred Income, Total	0	0
Nonperforming Financial Instruments [Member] | Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member]
Nonaccrual Loans	135	155
Loans 90+ Days Past Due Still Accruing	0	0
Loans and Leases Receivable, Net of Deferred Income, Total	135	155
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member]
Nonaccrual Loans	0	0
Loans 90+ Days Past Due Still Accruing	0	0
Loans and Leases Receivable, Net of Deferred Income, Total	0	0
Nonperforming Financial Instruments [Member] | Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member]
Nonaccrual Loans	348	0
Loans 90+ Days Past Due Still Accruing	0	0
Loans and Leases Receivable, Net of Deferred Income, Total	348	0
Nonperforming Financial Instruments [Member] | Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Nonaccrual Loans	0	0
Loans 90+ Days Past Due Still Accruing	0	0
Loans and Leases Receivable, Net of Deferred Income, Total	$ 0	$ 0