Note 4 - Loans and Leases - Loans by Loan Portfolio Class (Details) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018
Loans		$ 2,525,709	$ 2,548,171
Commercial and Industrial Portfolio Segment [Member]
Loans		827,747	833,524
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans	[1]	216,115	225,050
Undevelopment Land Portfolio Segment [Member]
Loans		28,433	30,092
Real Estate Mortgage Portfolio Segment [Member]
Loans		1,408,151	1,411,447
Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans		586,648	588,610
Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans		428,163	426,373
Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans		277,847	276,017
Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans		48,656	49,500
Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans		66,837	70,947
Consumer Portfolio Segment [Member]
Loans		$ 45,263	$ 48,058

[1] Consists of land acquired for development by the borrower, but for which no development has yet taken place.