Note 4 - Loans and Allowance for Loan Losses - Aging of Recorded Investment in Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Past Due	$ 3,872	$ 6,258
Current	504,710	466,605
Loans	508,879	473,187
Financial Asset Acquired with Credit Deterioration [Member]
Loans	297	324
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Past Due	2,625	4,406
Current	128,954	127,848
Loans	131,850	132,539
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] | Financial Asset Acquired with Credit Deterioration [Member]
Loans	271	285
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member]
Past Due	351	366
Current	17,110	18,948
Loans	17,461	19,314
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member] | Financial Asset Acquired with Credit Deterioration [Member]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member]
Past Due	0	0
Current	25,018	32,644
Loans	25,018	32,644
Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member] | Financial Asset Acquired with Credit Deterioration [Member]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member]
Past Due	155	146
Current	135,303	121,628
Loans	135,484	121,813
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Financial Asset Acquired with Credit Deterioration [Member]
Loans	26	39
Commercial Portfolio Segment [Member]
Past Due	0	119
Current	81,809	45,330
Loans	81,809	45,449
Commercial Portfolio Segment [Member] | Financial Asset Acquired with Credit Deterioration [Member]
Loans	0	0
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member]
Past Due	355	651
Current	52,922	55,337
Loans	53,277	55,988
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Financial Asset Acquired with Credit Deterioration [Member]
Loans	0	0
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Past Due	386	570
Current	63,594	64,870
Loans	63,980	65,440
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Financial Asset Acquired with Credit Deterioration [Member]
Loans	0	0
Financial Asset, 30 to 59 Days Past Due [Member]
Past Due	2,295	3,717
Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Past Due	1,672	2,572
Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member]
Past Due	130	185
Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member]
Past Due	0	0
Financial Asset, 30 to 59 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member]
Past Due	155	0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Past Due	0	61
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member]
Past Due	53	395
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Past Due	285	504
Financial Asset, 60 to 89 Days Past Due [Member]
Past Due	695	1,393
Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Past Due	227	824
Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member]
Past Due	65	101
Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member]
Past Due	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member]
Past Due	0	146
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Past Due	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member]
Past Due	302	256
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Past Due	101	66
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Past Due	882	1,148
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Past Due	726	1,010
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member]
Past Due	156	80
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member]
Past Due	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member]
Past Due	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Past Due	0	58
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member]
Past Due	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Past Due	$ 0	$ 0