Note 2 - Investments - Realized Gains and Losses Related to the Sale of Securities (Details) - USD ($)	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Gross gains	$ 17,014	$ 0
Gross losses	(35,556)	(476,146)
Net security losses	(18,542)	(476,146)
Increase in allowance for credit losses	(88,501)	(432,975)
Real Estate Loan [Member]
Mortgage loans on real estate	$ (88,501)	$ (432,975)

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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Amount of realized gain (loss) on investment in debt and equity securities.

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