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Note 7 - Investment Securities (Details Textual) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Mar. 31, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss		$ 4,500		$ 4,500		$ 5,500
Equity Securities, FV-NI, Unrealized Gain (Loss)		4,300	$ (6,200)	(6,204)	$ 9,298
Equity Securities, FV-NI, Current		$ 35,741		$ 35,741		$ 40,406
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions		177		177		192
Proceeds from Sale of Debt Securities, Available-for-Sale				$ 33,690	$ 0
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
Pledged Investment Securities		$ 18,400		18,400		$ 134,200
Signature Bank [Member]
Debt Securities, Available-for-Sale, Realized Loss	$ 3,000
Proceeds from Sale of Debt Securities, Available-for-Sale				$ 1,400
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions		149		149		154
Corporate Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions		18		18		24
Collateralized Mortgage Obligations [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions		5		5		5
US Government Corporations and Agencies Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions		5		5		8
US Treasury Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions						1

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