Fair Value of Financial Instruments (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
U.S. treasury securities	$ 10,883,041	$ 10,832,181
Corporate securities	47,462,245	46,451,905
Agency mortgage-backed securities	30,205,068	26,125,608
Equity securities	3,183,967	2,746,706
Short-term investments	2,949,946	200,000
Total financial instruments at fair value	94,684,267	86,356,400
Level 1
U.S. treasury securities	10,883,041	10,832,181
Corporate securities	0	0
Agency mortgage-backed securities	0	0
Equity securities	3,183,967	2,746,706
Short-term investments	2,949,946	200,000
Total financial instruments at fair value	17,016,954	13,778,887
Level 2
U.S. treasury securities	0	0
Corporate securities	47,462,245	46,451,905
Agency mortgage-backed securities	30,205,068	26,125,608
Equity securities	0	0
Short-term investments	0	0
Total financial instruments at fair value	77,667,313	72,577,513
Level 3
U.S. treasury securities	0	0
Corporate securities	0	0
Agency mortgage-backed securities	0	0
Equity securities	0	0
Short-term investments	0	0
Total financial instruments at fair value	$ 0	$ 0

Amount of equity securities categorized neither as held-to-maturity nor as trading.

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- Definition

The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings.

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-SubTopic 320
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Fair value of firm holdings in corporate fixed income securities. Includes pledged and unpledged holdings.

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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

+ References

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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Debt (bills, notes or bonds) that are issued by the government of the United States which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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