Investments - Investment Income (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Realized gains	$ (1,488,059)	$ 9,056,152	$ 2,143,695
Unrealized gains (losses)	5,348,243	15,086,747	(16,067,048)
Dividends	2,824,542	5,350,146	2,814,026
Interest	0	987,240	4,857,261
Other investment income (loss)	(99,877)	27,090	(20,612)
Net investment income (loss)	$ 6,584,849	$ 30,507,375	$ (6,272,678)

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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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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Amount of realized gain (loss) on investment.

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Amount of unrealized gain (loss) on investment.

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