Note 7 - Loans and Related Allowance for Loan and Lease Losses - Classes of the Loan Portfolio Summarized by Credit Quality (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Loans, total	$ 878,541	$ 609,140
Commercial And Industrial [Member]
Loans, total	99,314	60,630
Real Estate Construction Porfolio Segment [Member]
Loans, total	40,760	23,709
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans, total	316,191	270,830
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, total	403,135	249,490
Consumer Portfolio Segment [Member]
Loans, total	19,141	4,481
Pass [Member]
Loans, total	856,125	591,706
Pass [Member] \| Commercial And Industrial [Member]
Loans, total	92,855	58,539
Pass [Member] \| Real Estate Construction Porfolio Segment [Member]
Loans, total	40,737	23,541
Pass [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Loans, total	310,086	264,481
Pass [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, total	393,538	240,678
Pass [Member] \| Consumer Portfolio Segment [Member]
Loans, total	18,909	4,467
Special Mention [Member]
Loans, total	7,409	5,657
Special Mention [Member] \| Commercial And Industrial [Member]
Loans, total	2,188	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	744	428
Special Mention [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, total	4,477	4,422
Substandard [Member]
Loans, total	15,007	11,777
Substandard [Member] \| Commercial And Industrial [Member]
Loans, total	4,271	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	5,361	5,921
Substandard [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Loans, total	5,120	4,390
Substandard [Member] \| Consumer Portfolio Segment [Member]
Loans, total	232	$ 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