Investments - Investment Income (Expense) Comprised Primarily of Interest and Dividends (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]
Total investment income	$ 16,069	$ 13,366	$ 45,444	$ 36,504
Less: Investment expenses	(663)	(611)	(1,855)	(1,769)
Net investment income	15,406	12,755	43,589	34,735
Available-for-sale debt securities
Net Investment Income [Line Items]
Investment income	9,430	6,325	25,034	18,122
Equity securities
Net Investment Income [Line Items]
Investment income	864	953	2,600	2,874
Cash and cash equivalents
Net Investment Income [Line Items]
Investment income	5,689	5,961	17,397	15,113
Other
Net Investment Income [Line Items]
Investment income	$ 86	$ 127	$ 413	$ 395

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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Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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Amount of expenses related to the generation of investment income.

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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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