Note 11 - Commitments and Contingent Liabilities - Off Balance Sheet Commitments to Extend Credit (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Off balance sheet commitments to extend credit	$ 1,628,748	$ 1,390,772
Commercial and Industrial Loans [Member]
Off balance sheet commitments to extend credit	634,241	555,077
Construction and Development [Member]
Off balance sheet commitments to extend credit	285,376	266,550
Home Equity Loans [Member]
Off balance sheet commitments to extend credit	231,289	175,132
Credit Cards [Member]
Off balance sheet commitments to extend credit	39,200	32,321
Overdrafts [Member]
Off balance sheet commitments to extend credit	32,817	33,564
Letters of Credit [Member]
Off balance sheet commitments to extend credit	29,032	24,425
Other Off Balance Sheet Commitments [Member]
Off balance sheet commitments to extend credit	99,784	54,385
Future Loan Commitments [Member]
Off balance sheet commitments to extend credit	$ 277,009	$ 249,318