Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Net Investment Income [Line Items]
Gross investment income	$ 72,146	$ 60,737
Investment expenses	(2,925)	(2,284)
Net investment income	69,221	58,453
Fixed-maturities
Net Investment Income [Line Items]
Gross investment income	57,259	52,948
Equity securities
Net Investment Income [Line Items]
Gross investment income	2,539	2,932
Mortgage loans held for sale
Net Investment Income [Line Items]
Gross investment income	1,793	194
Short-term investments
Net Investment Income [Line Items]
Gross investment income	8,958	3,588
Other
Net Investment Income [Line Items]
Gross investment income	$ 1,597	$ 1,075

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, 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.

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