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Note 5 - Derivatives (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Unrealized Gain (Loss) on Derivatives	$ (3,258,000)	$ 3,324,000
Asset Pledged as Collateral [Member] | Interest Rate Swap Agreements [Member]
Securities Received as Collateral	0
Designated as Hedging Instrument [Member]
Investment Owned, Cost	187,700,000		$ 189,000,000
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	3,900,000		4,300,000
Derivative, Amount of Hedged Item	60,000,000		$ 60,000,000
Not Designated as Hedging Instrument [Member]
Unrealized Gain (Loss) on Derivatives	72,000	$ 201,000
Interest Rate Swap [Member]
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	$ 922,000

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Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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Cost of the investment.

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The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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