Note 15 - Commitments and Contingent Liabilities - Off Balance Sheet Commitments to Extend Credit (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Off balance sheet commitments to extend credit	$ 1,029,416	$ 834,604
Commercial and Industrial Loans [Member]
Off balance sheet commitments to extend credit	354,903	309,920
Commerical Construcition Loans [Member]
Off balance sheet commitments to extend credit	201,465	163,314
Residential Construction Loans [Member]
Off balance sheet commitments to extend credit	14,785	16,050
Home Equity Loans [Member]
Off balance sheet commitments to extend credit	149,584	147,907
Credit Cards [Member]
Off balance sheet commitments to extend credit	19,912	20,003
Overdrafts [Member]
Off balance sheet commitments to extend credit	21,558	21,751
Letters of Credit [Member]
Off balance sheet commitments to extend credit	20,374	20,891
Other Off Balance Sheet Commitments [Member]
Off balance sheet commitments to extend credit	33,748	33,369
Future Loan Commitments [Member]
Off balance sheet commitments to extend credit	$ 213,087	$ 101,399