Investments - Net Investment Income (loss) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Investment income (loss) from portfolios
Total investment income	$ 23,500	$ 20,828	$ 47,438	$ 41,178
Less: investment expenses	913	798	1,291	1,200
Net investment income	22,587	20,030	46,147	39,978
Available-for-sale securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	16,770	14,530	34,002	27,813
Equity securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	1,706	1,149	3,013	2,313
Limited partnerships
Investment income (loss) from portfolios
Limited partnerships	(16)	83	716	1,155
Agent loans
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	2,030	1,557	3,934	3,001
Cash equivalents and other
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	$ 3,010	$ 3,509	$ 5,773	$ 6,896

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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