Note 3 - Loans and Allowance for Credit Losses on Loans - Credit Card Loan Payment Activity (Details) - USD ($) $ in Thousands		Jun. 30, 2023	Dec. 31, 2022
Loans	[1]	$ 5,418,609	$ 5,205,918
Credit Card Receivable [Member]
Loans		22,190	20,413
Commercial Portfolio Segment [Member] | Credit Card Receivable [Member]
Loans		22,190	20,413
Commercial Portfolio Segment [Member] | Credit Card Receivable [Member] | Performing Financial Instruments [Member]
Loans		22,174	20,413
Commercial Portfolio Segment [Member] | Credit Card Receivable [Member] | Nonperforming Financial Instruments [Member]
Loans		$ 16	$ 0

[1] Total loans are presented inclusive of premiums, discounts and net loan origination fees and costs.