Note 20 - Concentrations of Credit - (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Loans and Leases Receivable, Net of Deferred Income, Total	$ 1,710,265	$ 1,528,469
Commercial Real Estate Portfolio Segment [Member] | Nonfarm Nonresidential [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	$ 612,608	$ 518,660
Commercial Real Estate Portfolio Segment [Member] | Nonfarm Nonresidential [Member] | Loan Secured by Real Estate [Member] | Credit Concentration Risk [Member]
Concentration Risk, Percentage	35.80%	33.90%
Commercial Real Estate Portfolio Segment [Member] | Construction and Land [Member]
Loans and Leases Receivable, Net of Deferred Income, Total	$ 244,181	$ 211,054
Commercial Real Estate Portfolio Segment [Member] | Construction and Land [Member] | Loan Secured by Real Estate [Member] | Credit Concentration Risk [Member]
Concentration Risk, Percentage	14.30%	13.80%