Note 2 - Investments - Amortized Cost and Fair Value of Available-for-sale and Held-to-maturity Investments (Details) - USD ($)	Mar. 31, 2026	Dec. 31, 2025
Cost or Amortized Cost	$ 92,469,798	$ 90,036,854
Debt securities, gross unrealized gains	562,345	873,964
Debt Securities, Gross Unrealized Losses	(4,768,730)	(4,376,114)
Debt securities, fair value	88,263,413	86,534,704
US Treasury Securities [Member]
Cost or Amortized Cost	809,794	810,255
Debt securities, gross unrealized gains	0	1,562
Debt Securities, Gross Unrealized Losses	(82,997)	(78,925)
Debt securities, fair value	726,797	732,892
Corporate Debt Securities [Member]
Cost or Amortized Cost	30,375,995	30,702,897
Debt securities, gross unrealized gains	102,327	218,634
Debt Securities, Gross Unrealized Losses	(2,919,393)	(2,622,315)
Debt securities, fair value	27,558,929	28,299,216
US States and Political Subdivisions Debt Securities [Member]
Cost or Amortized Cost	6,328,396	6,341,809
Debt securities, gross unrealized gains	130	1,735
Debt Securities, Gross Unrealized Losses	(574,165)	(536,408)
Debt securities, fair value	5,754,361	5,807,136
Redeemable Preferred Stock [Member]
Cost or Amortized Cost	1,669,244	2,142,141
Debt securities, gross unrealized gains	0	3,788
Debt Securities, Gross Unrealized Losses	(177,443)	(147,491)
Debt securities, fair value	1,491,801	1,998,438
Term Loans [Member]
Cost or Amortized Cost	12,244,604	11,187,284
Debt securities, gross unrealized gains	30,171	10,032
Debt Securities, Gross Unrealized Losses	(181,390)	(191,512)
Debt securities, fair value	12,093,385	11,005,804
Collateralized Mortgage-Backed Securities [Member]
Cost or Amortized Cost	41,041,765	38,852,468
Debt securities, gross unrealized gains	429,717	638,213
Debt Securities, Gross Unrealized Losses	(833,342)	(799,463)
Debt securities, fair value	$ 40,638,140	$ 38,691,218