Note 7 - Loans and Related Allowance for Loan Losses - Classes of the Loan Portfolio Summarized by Credit Quality (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Loans, total	$ 837,158	$ 609,140
Commercial And Industrial [Member]
Loans, total	91,777	60,630
Real Estate Construction Porfolio Segment [Member]
Loans, total	29,238	23,709
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans, total	300,508	270,830
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, total	395,102	249,490
Consumer Portfolio Segment [Member]
Loans, total	20,533	4,481
Pass [Member]
Loans, total	815,619	591,706
Pass [Member] \| Commercial And Industrial [Member]
Loans, total	85,248	58,539
Pass [Member] \| Real Estate Construction Porfolio Segment [Member]
Loans, total	29,215	23,541
Pass [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans, total	294,284	264,481
Pass [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, total	386,346	240,678
Pass [Member] \| Consumer Portfolio Segment [Member]
Loans, total	20,526	4,467
Special Mention [Member]
Loans, total	6,463	5,657
Special Mention [Member] \| Commercial And Industrial [Member]
Loans, total	2,051	663
Special Mention [Member] \| Real Estate Construction Porfolio Segment [Member]
Loans, total		144
Special Mention [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans, total	568	428
Special Mention [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, total	3,844	4,422
Substandard [Member]
Loans, total	15,076	11,777
Substandard [Member] \| Commercial And Industrial [Member]
Loans, total	4,478	1,428
Substandard [Member] \| Real Estate Construction Porfolio Segment [Member]
Loans, total	23	24
Substandard [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans, total	5,656	5,921
Substandard [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, total	4,912	4,390
Substandard [Member] \| Consumer Portfolio Segment [Member]
Loans, total	7	$ 14
Doubtful [Member]
Loans, total
Doubtful [Member] \| Commercial And Industrial [Member]
Loans, total
Doubtful [Member] \| Real Estate Construction Porfolio Segment [Member]
Loans, total
Doubtful [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans, total
Doubtful [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, total