Fair Value Measurements - Schedule of Assets Recorded at Fair Value on a Recurring Basis (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
U.S. government treasury securities	$ 943,130	$ 967,770
U.S. government agency securities	44,053,754	43,860,090
State and municipal securities	7,387,960	7,573,689
Residential mortgage-backed securities	3,742,706	1,861,712
Total	56,127,550	54,263,261
Level 1 [Member]
U.S. government treasury securities	943,130	967,770
U.S. government agency securities	0	0
State and municipal securities	0	0
Residential mortgage-backed securities	0	0
Total	943,130	967,770
Level 2 [Member]
U.S. government treasury securities	0	0
U.S. government agency securities	44,053,754	43,860,090
State and municipal securities	7,387,960	7,573,689
Residential mortgage-backed securities	3,742,706	1,861,712
Total	55,184,420	53,295,491
Level 3 [Member]
U.S. government treasury securities	0	0
U.S. government agency securities	0	0
State and municipal securities	0	0
Residential mortgage-backed securities	0	0
Total	$ 0	$ 0

Financial Instruments Owned US Government Treasury Securities At Fair Value.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

+ Details

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- Definition

The fair value as of the balance sheet date of firm holdings in mortgages, mortgage backed securities (investment instruments that represent ownership of an undivided interest in a group of mortgages, where principal and interest from the individual mortgages are used to pay investors' principal and interest on the mortgage backed security) and asset-backed securities that are primarily paid from the cash flows of a discrete pool of receivables or other financial assets (such as credit-card receivables), either fixed or revolving, that by their terms convert into cash within a finite time period. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

+ References

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- Definition

The fair value as of the balance sheet date of firm holdings in fixed income obligations issued by state and local governments and authorities. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

+ References

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- Definition

The fair value as of the balance sheet date of firm holdings in debt obligations issued by the US government including short-term Treasury bills, medium-term Treasury notes, and long-term Treasury bonds, as well as debt issued by agencies. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

+ References

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