Note 2 - Investments - Gross Unrealized Losses (Details) - USD ($)	Jun. 30, 2026	Dec. 31, 2025
Available-for-sale securities, less than 12 months, fair value	$ 27,987,976	$ 24,036,504
Available-for-sale securities, less than 12 months, unrealized loss	(285,506)	(328,909)
US Treasury securities	26,080,329	31,461,798
US Treasury securities	(4,156,260)	(4,047,205)
Available-for-sale securities, fair value	54,068,305	55,498,302
Debt Securities, Gross Unrealized Loss	(4,441,766)	(4,376,114)
US Treasury Securities [Member]
Available-for-sale securities, less than 12 months, fair value	448,093	0
Available-for-sale securities, less than 12 months, unrealized loss	(2,808)	0
US Treasury securities	281,741	280,278
US Treasury securities	(85,600)	(78,925)
Available-for-sale securities, fair value	729,834	280,278
Debt Securities, Gross Unrealized Loss	(88,408)	(78,925)
Corporate Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	11,180,867	8,857,877
Available-for-sale securities, less than 12 months, unrealized loss	(123,607)	(122,197)
US Treasury securities	11,495,820	12,403,317
US Treasury securities	(2,578,563)	(2,500,118)
Available-for-sale securities, fair value	22,676,687	21,261,194
Debt Securities, Gross Unrealized Loss	(2,702,170)	(2,622,315)
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	1,230,074	1,163,445
Available-for-sale securities, less than 12 months, unrealized loss	(31,709)	(27,032)
US Treasury securities	4,049,671	4,293,247
US Treasury securities	(538,687)	(509,376)
Available-for-sale securities, fair value	5,279,745	5,456,692
Debt Securities, Gross Unrealized Loss	(570,396)	(536,408)
Redeemable Preferred Stock [Member]
Available-for-sale securities, less than 12 months, fair value	74,719	0
Available-for-sale securities, less than 12 months, unrealized loss	(54)	0
US Treasury securities	1,357,520	1,521,302
US Treasury securities	(165,135)	(147,491)
Available-for-sale securities, fair value	1,432,239	1,521,302
Debt Securities, Gross Unrealized Loss	(165,189)	(147,491)
Term Loans [Member]
Available-for-sale securities, less than 12 months, fair value	796,505	897,477
Available-for-sale securities, less than 12 months, unrealized loss	(3,581)	(1,338)
US Treasury securities	4,139,293	6,843,379
US Treasury securities	(157,477)	(190,174)
Available-for-sale securities, fair value	4,935,798	7,740,856
Debt Securities, Gross Unrealized Loss	(161,058)	(191,512)
Collateralized Mortgage-Backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	14,257,718	13,117,705
Available-for-sale securities, less than 12 months, unrealized loss	(123,747)	(178,342)
US Treasury securities	4,756,284	6,120,275
US Treasury securities	(630,798)	(621,121)
Available-for-sale securities, fair value	19,014,002	19,237,980
Debt Securities, Gross Unrealized Loss	$ (754,545)	$ (799,463)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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