Note 4 - Loans and Allowance for Loan Losses - Recorded Investment in Loans by Risk Category (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Loans	$ 439,855	$ 414,617
Pass [Member]
Loans	431,650	405,806
Special Mention [Member]
Loans	2,510	3,623
Substandard [Member]
Loans	2,569	2,640
Doubtful [Member]
Loans	3,126	2,548
Unlikely to be Collected Financing Receivable [Member]
Loans
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Loans	137,019	136,960
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] | Pass [Member]
Loans	133,878	133,618
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] | Special Mention [Member]
Loans	133	348
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] | Substandard [Member]
Loans	1,168	684
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] | Doubtful [Member]
Loans	1,840	2,310
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member]
Loans	22,744	18,309
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member] | Pass [Member]
Loans	22,458	18,003
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member] | Special Mention [Member]
Loans	65	157
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member] | Substandard [Member]
Loans	69	149
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member] | Doubtful [Member]
Loans	152
Real Estate Mortgage Portfolio Segment [Member] | Land Loan [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans
Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member]
Loans	25,442	21,034
Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member] | Pass [Member]
Loans	24,921	20,173
Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member] | Special Mention [Member]
Loans		861
Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member] | Substandard [Member]
Loans
Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member] | Doubtful [Member]
Loans	521
Real Estate Mortgage Portfolio Segment [Member] | Construction Loans [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member]
Loans	107,672	100,340
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Pass [Member]
Loans	104,843	97,219
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Special Mention [Member]
Loans	1,520	1,362
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Substandard [Member]
Loans	938	1,620
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Doubtful [Member]
Loans	371	139
Real Estate Mortgage Portfolio Segment [Member] | Commercial Real Estate Loan [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans
Commercial Portfolio Segment [Member]
Loans	36,417	34,203
Commercial Portfolio Segment [Member] | Pass [Member]
Loans	35,162	33,245
Commercial Portfolio Segment [Member] | Special Mention [Member]
Loans	763	734
Commercial Portfolio Segment [Member] | Substandard [Member]
Loans	285	182
Commercial Portfolio Segment [Member] | Doubtful [Member]
Loans	207	42
Commercial Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member]
Loans	53,003	50,978
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Pass [Member]
Loans	52,859	50,919
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Special Mention [Member]
Loans
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Substandard [Member]
Loans	109	2
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Doubtful [Member]
Loans	35	57
Consumer Portfolio Segment [Member] | Home Equity and Second Mortgage [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member]
Loans	57,558	52,793
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Pass [Member]
Loans	57,529	52,629
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Special Mention [Member]
Loans	29	161
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Substandard [Member]
Loans		3
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Doubtful [Member]
Loans
Consumer Portfolio Segment [Member] | All Other Consumer Excluding Home Equity and Second Mortgage [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans