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Note 3 - Investment Securities (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 33,690	$ 0	$ 0
Debt Securities, Available-for-Sale, Realized Gain	1,100
Debt Securities, Available-for-Sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-Sale, Transfer in, Allowance for Credit Loss, Expense	$ 0	$ 0
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	182	192
Debt Securities, Available-for-Sale	$ 1,547,128	$ 1,604,570
Equity Securities, FV-NI, Current	34,429	40,406
Equity Securities, FV-NI, Unrealized Gain (Loss)	(7,516)	18,248	291
Proceeds from Sale, Debt Security, Trading, and Equity Security, FV-NI, Held-for-Investment	0	0	553
Equity Securities, FV-NI, Realized Gain (Loss)			$ (101)
Asset Pledged as Collateral [Member] | Public Deposits and Other Borrowings [Member]
Debt Securities, Available-for-Sale	$ 17,800	$ 134,200
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	154	154
Debt Securities, Available-for-Sale	$ 684,016	$ 786,723
Corporate Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	16	24
Debt Securities, Available-for-Sale	$ 207,945	$ 246,334
US Government Corporations and Agencies Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	9	8
Debt Securities, Available-for-Sale	$ 9,149	$ 48,169
Collateralized Mortgage Obligations [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	3	5
Debt Securities, Available-for-Sale	$ 24,556	$ 28,044
US Treasury Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions		1
Debt Securities, Available-for-Sale	$ 621,462	$ 495,300

X

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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