Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Investment income (loss) from portfolios
Total investment income	$ 20,828	$ 16,431	$ 41,178	$ 32,735
Less: investment expenses	798	421	1,200	822
Net investment income	20,030	16,010	39,978	31,913
Available-for-sale securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	14,530	12,107	27,813	23,720
Equity securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	1,149	1,199	2,313	2,417
Limited partnerships
Investment income (loss) from portfolios
Limited partnerships	83	(264)	1,155	261
Agent loans
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	1,557	908	3,001	1,821
Cash equivalents and other
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	$ 3,509	$ 2,481	$ 6,896	$ 4,516

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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