Note 8 - Short-term Borrowings (Details Textual) $ in Millions	Dec. 31, 2023 USD ($)
Federal Home Loan Bank Advances [Member]
Line of Credit Facility, Remaining Borrowing Capacity	$ 656.8
Correspondent Banks [Member]
Line of Credit Facility, Remaining Borrowing Capacity	20.0
Federal Reserve Bank Discount Window [Member]
Line of Credit Facility, Remaining Borrowing Capacity	70.4
Collateral for Federal Reserve Bank Term Funding Program [Member] | Asset Pledged as Collateral [Member]
Marketable Securities	$ 59.7