Investments - Net Investment Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Net Investment Income [Line Items]
Gross investment income	$ 304,359	$ 268,412	$ 202,524
Investment expenses	(11,666)	(9,982)	(6,866)
Net investment income	292,693	258,430	195,658
Fixed-maturities
Net Investment Income [Line Items]
Gross investment income	231,769	226,654	184,189
Equity securities
Net Investment Income [Line Items]
Gross investment income	12,003	13,420	11,210
Residential mortgage loans held for sale
Net Investment Income [Line Items]
Gross investment income	22,569	4,212	39
Short-term investments
Net Investment Income [Line Items]
Gross investment income	31,736	18,840	5,716
Other
Net Investment Income [Line Items]
Gross investment income	$ 6,282	$ 5,286	$ 1,370

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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