Note 2 - Investments - Amortized Cost and Fair Value of Available-for-sale and Held-to-maturity Investments (Details) - USD ($)	Jun. 30, 2022	Dec. 31, 2021
Cost or Amortized Cost	$ 35,888,401	$ 35,256,039
Debt Securities, Gross Unrealized Gains	105,344
Debt Securities, Gross Unrealized Losses	(3,795,537)	(283,345)
Investments in available-for-sale securities, at fair value	32,198,208	37,942,657
Debt Securities, Gross Unrealized Gain		2,969,963
US Treasury Securities [Member]
Cost or Amortized Cost	303,451	303,195
Debt Securities, Gross Unrealized Gains	55,858
Debt Securities, Gross Unrealized Losses	0	0
Investments in available-for-sale securities, at fair value	359,309	447,765
Debt Securities, Gross Unrealized Gain		144,570
Corporate Debt Securities [Member]
Cost or Amortized Cost	19,563,739	19,397,461
Debt Securities, Gross Unrealized Gains	11,855
Debt Securities, Gross Unrealized Losses	(2,344,887)	(177,700)
Investments in available-for-sale securities, at fair value	17,230,707	21,321,279
Debt Securities, Gross Unrealized Gain		2,101,518
US States and Political Subdivisions Debt Securities [Member]
Cost or Amortized Cost	5,911,439	6,306,387
Debt Securities, Gross Unrealized Gains	36,258
Debt Securities, Gross Unrealized Losses	(386,509)	(14,292)
Investments in available-for-sale securities, at fair value	5,561,188	6,963,358
Debt Securities, Gross Unrealized Gain		671,263
Redeemable Preferred Stock [Member]
Cost or Amortized Cost	4,044,005	3,612,625
Debt Securities, Gross Unrealized Gains	0
Debt Securities, Gross Unrealized Losses	(495,473)	(21,094)
Investments in available-for-sale securities, at fair value	3,548,532	3,621,526
Debt Securities, Gross Unrealized Gain		29,995
Collateralized Mortgage-Backed Securities [Member]
Cost or Amortized Cost	6,065,767	5,636,371
Debt Securities, Gross Unrealized Gains	1,373
Debt Securities, Gross Unrealized Losses	(568,668)	(70,259)
Investments in available-for-sale securities, at fair value	$ 5,498,472	5,588,729
Debt Securities, Gross Unrealized Gain		$ 22,617

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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-SubTopic 10
-Section 50
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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