Note 20 - Concentrations of Credit - (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Loans and Leases Receivable, Net of Deferred Income, Total	$ 1,528,469	$ 975,284
Commercial Real Estate Portfolio Segment [Member] | Nonfarm Nonresidential [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	$ 518,660	$ 337,699
Commercial Real Estate Portfolio Segment [Member] | Nonfarm Nonresidential [Member] | Loan Secured by Real Estate [Member] | Credit Concentration Risk [Member]
Concentration Risk, Percentage	33.90%	34.60%
Commercial Real Estate Portfolio Segment [Member] | Construction and Land [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	$ 211,054	$ 143,535
Commercial Real Estate Portfolio Segment [Member] | Construction and Land [Member] | Loan Secured by Real Estate [Member] | Credit Concentration Risk [Member]
Concentration Risk, Percentage	13.80%	14.70%