Fair Vaule of Financial Instruments - Fair Value of Invested Assets (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
U.S. treasury securities	$ 10,832,181	$ 15,235,332
Corporate securities	46,451,905	43,029,333
Agency mortgage-backed securities	26,125,608	25,235,045
Equity securities	2,746,706	0
Short-term investments	200,000	2,196,815
Total financial instruments	86,356,400	85,696,525
Level 1
U.S. treasury securities	10,832,181	15,235,332
Corporate securities	0	0
Agency mortgage-backed securities	0	0
Equity securities	2,746,706
Short-term investments	200,000	2,196,815
Total financial instruments	13,778,887	17,432,147
Level 2
U.S. treasury securities	0	0
Corporate securities	46,451,905	43,029,333
Agency mortgage-backed securities	26,125,608	25,235,045
Equity securities	0
Short-term investments	0	0
Total financial instruments	72,577,513	68,264,378
Level 3
U.S. treasury securities	0	0
Corporate securities	0	0
Agency mortgage-backed securities	0	0
Equity securities	0
Short-term investments	0	0
Total financial instruments	$ 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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969

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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

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(4))
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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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