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Investments - Investment Income (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Realized gains	$ 9,056,152	$ 2,143,695	$ 2,497,707
Unrealized gains (losses)	15,086,747	(16,067,048)	8,077,335
Dividends	5,350,146	2,814,026	2,248,185
Interest	987,240	4,857,261	1,195,995
Other investment income (loss)	27,090	(20,612)	(1,629)
Net investment income (loss)	$ 30,507,375	$ (6,272,678)	$ 14,017,593

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Investment Income, Other Income (Loss)

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Amount of dividend income on nonoperating securities.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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