Investments - Net Investment Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Components of net investment income
Gross investment income	$ 84,982	$ 87,243	$ 66,926
Investment expenses	(4,895)	(3,701)	(2,835)
Net investment income	80,087	83,542	64,091
Fixed maturities
Components of net investment income
Gross investment income	83,313	82,194	63,053
Short-term investments
Components of net investment income
Gross investment income	$ 1,669	$ 5,049	$ 3,873

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Amount of expenses related to the generation of investment income.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

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