Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Net Investment Income [Line Items]
Gross investment income	$ 81,434	$ 70,253	$ 230,100	$ 196,741
Investment expenses	(3,038)	(2,448)	(8,717)	(7,135)
Net investment income	78,396	67,805	221,383	189,606
Fixed-maturities
Net Investment Income [Line Items]
Gross investment income	59,348	58,599	174,531	167,985
Equity securities
Net Investment Income [Line Items]
Gross investment income	3,047	3,222	8,653	9,667
Mortgage loans held for sale
Net Investment Income [Line Items]
Gross investment income	7,828	1,719	15,032	2,487
Short-term investments
Net Investment Income [Line Items]
Gross investment income	9,686	5,405	27,258	12,969
Other
Net Investment Income [Line Items]
Gross investment income	$ 1,525	$ 1,308	$ 4,626	$ 3,633

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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