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
Net Investment Income [Line Items]
Gross investment income	$ 76,520	$ 65,751	$ 148,666	$ 126,488
Investment expenses	(2,754)	(2,403)	(5,679)	(4,687)
Net investment income	73,766	63,348	142,987	121,801
Fixed-maturities
Net Investment Income [Line Items]
Gross investment income	57,924	56,439	115,183	109,387
Equity securities
Net Investment Income [Line Items]
Gross investment income	3,067	3,512	5,606	6,444
Mortgage loans held for sale
Net Investment Income [Line Items]
Gross investment income	5,411	574	7,204	768
Short-term investments
Net Investment Income [Line Items]
Gross investment income	8,614	3,976	17,572	7,564
Other
Net Investment Income [Line Items]
Gross investment income	$ 1,504	$ 1,250	$ 3,101	$ 2,325

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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