Note 6 - Investments, Available for Sale ("AFS") - Available for Sale Securities Classified by Contractual Maturity Date (Details) - USD ($)	Sep. 30, 2023	Dec. 31, 2022
One Year or Less, amortized cost, AFS	$ 13,693
One Year or Less, fair value, AFS	13,525
After One – Five Years, amortized cost, AFS	6,593,553
After One – Five Years, fair value, AFS	6,546,193
After Five – Ten Years, amortized cost, AFS	76,090,051
After Five – Ten Years, fair value, AFS	69,654,980
More Than Ten Years, amortized cost, AFS	137,437,473
More Than Ten Years, fair value, AFS	123,089,327
Amortized cost, AFS	591,931,230	$ 604,157,308
Available For Sale ("AFS")	531,421,573	550,148,284
Collateralized Mortgage-Backed Securities [Member]
Amortized cost, AFS	371,796,460	353,223,361
Available For Sale ("AFS")	$ 332,117,548	$ 319,281,268

Amortized cost 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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