Note 5 - Loans - Loans by Credit Quality Indicator (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Loans	$ 826,356	$ 835,207
Commercial Loans [Member]
Loans	546,960	520,847
Accruing Loans [Member]
Loans	277,413	313,278
Nonaccrual Loans [Member]
Loans	1,982	1,082
Subtotal, Other Loans [Member]
Loans	279,395	314,360
Pass [Member] | Commercial Loans [Member]
Loans	532,300	499,208
Special Mention [Member] | Commercial Loans [Member]
Loans	2,271	8,007
Substandard [Member] | Commercial Loans [Member]
Loans	12,390	13,632
Doubtful [Member] | Commercial Loans [Member]
Loans		0
Unlikely to be Collected Financing Receivable [Member] | Commercial Loans [Member]
Loans		0
Residential Portfolio Segment [Member]
Loans	170,723	164,833
Residential Portfolio Segment [Member] | Commercial Loans [Member]
Loans	32,703	34,018
Residential Portfolio Segment [Member] | Accruing Loans [Member]
Loans	136,709	130,132
Residential Portfolio Segment [Member] | Nonaccrual Loans [Member]
Loans	1,311	683
Residential Portfolio Segment [Member] | Subtotal, Other Loans [Member]
Loans	138,020	130,815
Residential Portfolio Segment [Member] | Pass [Member] | Commercial Loans [Member]
Loans	32,219	33,573
Residential Portfolio Segment [Member] | Special Mention [Member] | Commercial Loans [Member]
Loans	177	291
Residential Portfolio Segment [Member] | Substandard [Member] | Commercial Loans [Member]
Loans	307	154
Residential Portfolio Segment [Member] | Doubtful [Member] | Commercial Loans [Member]
Loans	0	0
Residential Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Loans [Member]
Loans	0	0
Commercial Real Estate Portfolio Segment [Member]
Loans	278,379	262,778
Commercial Real Estate Portfolio Segment [Member] | Commercial Loans [Member]
Loans	278,379	262,778
Commercial Real Estate Portfolio Segment [Member] | Accruing Loans [Member]
Loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Nonaccrual Loans [Member]
Loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Subtotal, Other Loans [Member]
Loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Pass [Member] | Commercial Loans [Member]
Loans	266,112	250,674
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member] | Commercial Loans [Member]
Loans	1,668	1,858
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member] | Commercial Loans [Member]
Loans	10,599	10,246
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member] | Commercial Loans [Member]
Loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Loans [Member]
Loans	0	0
Construction, Land Acquisition and Development [Member]
Loans	47,484	20,813
Construction, Land Acquisition and Development [Member] | Commercial Loans [Member]
Loans	46,361	18,461
Construction, Land Acquisition and Development [Member] | Accruing Loans [Member]
Loans	1,123	2,352
Construction, Land Acquisition and Development [Member] | Nonaccrual Loans [Member]
Loans	0	0
Construction, Land Acquisition and Development [Member] | Subtotal, Other Loans [Member]
Loans	1,123	2,352
Construction, Land Acquisition and Development [Member] | Pass [Member] | Commercial Loans [Member]
Loans	46,361	17,704
Construction, Land Acquisition and Development [Member] | Special Mention [Member] | Commercial Loans [Member]
Loans	0	0
Construction, Land Acquisition and Development [Member] | Substandard [Member] | Commercial Loans [Member]
Loans	0	757
Construction, Land Acquisition and Development [Member] | Doubtful [Member] | Commercial Loans [Member]
Loans	0	0
Construction, Land Acquisition and Development [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Loans [Member]
Loans	0	0
Commercial and Industrial [Member]
Loans	147,623	150,962
Commercial and Industrial [Member] | Commercial Loans [Member]
Loans	142,499	144,529
Commercial and Industrial [Member] | Accruing Loans [Member]
Loans	5,124	6,421
Commercial and Industrial [Member] | Nonaccrual Loans [Member]
Loans	0	12
Commercial and Industrial [Member] | Subtotal, Other Loans [Member]
Loans	5,124	6,433
Commercial and Industrial [Member] | Pass [Member] | Commercial Loans [Member]
Loans	140,589	137,888
Commercial and Industrial [Member] | Special Mention [Member] | Commercial Loans [Member]
Loans	426	4,193
Commercial and Industrial [Member] | Substandard [Member] | Commercial Loans [Member]
Loans	1,484	2,448
Commercial and Industrial [Member] | Doubtful [Member] | Commercial Loans [Member]
Loans	0	0
Commercial and Industrial [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Loans [Member]
Loans	0	0
Consumer Portfolio Segment [Member]
Loans	138,239	176,784
Consumer Portfolio Segment [Member] | Commercial Loans [Member]
Loans	3,111	2,024
Consumer Portfolio Segment [Member] | Accruing Loans [Member]
Loans	134,457	174,373
Consumer Portfolio Segment [Member] | Nonaccrual Loans [Member]
Loans	671	387
Consumer Portfolio Segment [Member] | Subtotal, Other Loans [Member]
Loans	135,128	174,760
Consumer Portfolio Segment [Member] | Pass [Member] | Commercial Loans [Member]
Loans	3,111	2,024
Consumer Portfolio Segment [Member] | Special Mention [Member] | Commercial Loans [Member]
Loans	0	0
Consumer Portfolio Segment [Member] | Substandard [Member] | Commercial Loans [Member]
Loans	0	0
Consumer Portfolio Segment [Member] | Doubtful [Member] | Commercial Loans [Member]
Loans	0	0
Consumer Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Loans [Member]
Loans	0	0
State and Political Subdivisions [Member]
Loans	43,908	59,037
State and Political Subdivisions [Member] | Commercial Loans [Member]
Loans	43,908	59,037
State and Political Subdivisions [Member] | Accruing Loans [Member]
Loans		0
State and Political Subdivisions [Member] | Nonaccrual Loans [Member]
Loans		0
State and Political Subdivisions [Member] | Subtotal, Other Loans [Member]
Loans		0
State and Political Subdivisions [Member] | Pass [Member] | Commercial Loans [Member]
Loans	43,908	57,345
State and Political Subdivisions [Member] | Special Mention [Member] | Commercial Loans [Member]
Loans		1,665
State and Political Subdivisions [Member] | Substandard [Member] | Commercial Loans [Member]
Loans		27
State and Political Subdivisions [Member] | Doubtful [Member] | Commercial Loans [Member]
Loans		0
State and Political Subdivisions [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Loans [Member]
Loans		$ 0