Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Investment income (loss) from portfolios
Total investment income	$ 21,641	$ 17,893	$ 62,819	$ 50,628
Less: investment expenses	608	571	1,808	1,393
Net investment income	21,033	17,322	61,011	49,235
Available-for-sale securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	14,068	12,891	41,881	36,611
Equity securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	1,220	1,119	3,533	3,536
Limited partnerships
Investment income (loss) from portfolios
Limited partnerships	114	(127)	1,269	134
Agent loans
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	1,633	1,070	4,634	2,891
Cash equivalents and other
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	$ 4,606	$ 2,940	$ 11,502	$ 7,456

Interest and Dividend Income, Operating and Income (Loss) from Equity Method Investments

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Amount, after investment expense, of income earned from investments in securities, limited partnerships and loan receivables. Includes, but is not limited to, dividends, interest, and amount of income (loss) for proportionate share of equity method investee's income (loss).

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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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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