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Note 5 - Derivatives (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Unrealized Gain (Loss) on Derivatives			$ (5,316,000)	$ 3,598,000
Asset Pledged as Collateral [Member] | Interest Rate Swap Agreements [Member]
Securities Received as Collateral	$ 0		0
Designated as Hedging Instrument [Member]
Investment Owned, Cost	185,000,000		185,000,000		$ 189,000,000
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	2,400,000		2,400,000		4,300,000
Derivative, Amount of Hedged Item	60,000,000		60,000,000		$ 60,000,000
Not Designated as Hedging Instrument [Member]
Unrealized Gain (Loss) on Derivatives	197,000	$ 19,000	269,000	$ 201,000
Interest Rate Swap [Member]
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	$ 563,000,000,000		$ 563,000,000,000

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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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