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Note 8 - Deposits and Borrowed Funds (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Demand Deposit Overdrafts	$ 1,053		$ 1,053		$ 620
Interest Expense, Time Deposits, $100,000 or More	20	$ 31	41	$ 65
Bank Term Funding Program [Member]
Proceeds from Lines of Credit			200,000
Federal Reserve [Member]
Line of Credit Facility, Maximum Borrowing Capacity	867,510		867,510
Line of Credit Facility, Average Outstanding Amount			131,291
Federal Reserve [Member] \| Asset Pledged as Collateral [Member]
Available for Sale and Held to Maturity Debt Securities	$ 1,462,966		1,462,966
Bank Term Funding Program [Member] \| Borrowings Maturing February 2025 [Member]
Proceeds from Lines of Credit			80,000
Bank Term Funding Program [Member] \| Borrowings Maturing March 2025 [Member]
Proceeds from Lines of Credit			$ 120,000