Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Components of net investment income
Gross investment income	$ 57,199	$ 47,073	$ 110,630	$ 92,268
Investment expenses	(1,113)	(1,823)	(2,459)	(3,782)
Net investment income	56,086	45,250	108,171	88,486
Fixed maturities
Components of net investment income
Gross investment income	45,368	43,775	91,656	87,251
Short-term investments
Components of net investment income
Gross investment income	$ 11,831	$ 3,298	$ 18,974	$ 5,017

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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