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Investments - Additional Information (Detail)		12 Months Ended
	Nov. 30, 2013 USD ($)	Dec. 31, 2019 USD ($) Securities	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Schedule of Investments [Line Items]
Net unrealized losses arising prior to reclassification date	$ 15,100,000
Amortization of unrealized losses recorded in accumulated other comprehensive income (loss)		$ 1,200,000
Accumulated other comprehensive loss		504,170	$ (14,228,059)
Impairment losses		0	0	$ 0
Sales or transfers, held to maturity		0	0	0
Derivative instruments or hedging activities		0	0	$ 0
Amortized cost of fixed maturities on deposit with various regulatory authorities		8,330,651	8,795,334
Unrealised Gains on Equity Securities		12,179,912	4,817,917
Unrealised Loss on Equity Securities		121,492	2,093,624
Equity [Member]
Schedule of Investments [Line Items]
Unrealised Gains on Equity Securities		8,900,000	1,200,000
Unrealised Loss on Equity Securities		25,751	4,400,000
Obligations of States and Political Subdivisions [Member]
Schedule of Investments [Line Items]
Aggregate fair value of bond held		182,000,000	157,700,000
Amortized cost of bond held		172,300,000	152,200,000
Special Revenue Bonds [Member]
Schedule of Investments [Line Items]
Aggregate fair value of bond held		93,400,000	84,300,000
Amortized cost of bond held		$ 87,500,000	$ 80,900,000
Education Bonds [Member]
Schedule of Investments [Line Items]
Percentage of investments in special revenue bonds		44.00%	49.00%
Water and Sewer Utility Bonds [Member]
Schedule of Investments [Line Items]
Percentage of investments in special revenue bonds		35.00%	29.00%
Fixed Maturities [Member]
Schedule of Investments [Line Items]
Number of fixed maturity securities classified as available for sale | Securities		136
Accumulated Net Unrealized Investment Losses [Member]
Schedule of Investments [Line Items]
Accumulated other comprehensive loss		$ 7,500,000	$ 8,600,000
Minimum [Member]
Schedule of Investments [Line Items]
Percentage of which the company held security of any issuer		10.00%	10.00%

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