Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Investment income (loss) from portfolios
Total investment income	$ 23,938	$ 20,350
Less: investment expenses	378	402
Net investment income	23,560	19,948
Available-for-sale securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	17,232	13,283
Equity securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	1,307	1,164
Limited partnerships
Investment income (loss) from portfolios
Limited partnerships	732	1,072
Agent loans
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	1,904	1,444
Cash equivalents and other
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	$ 2,763	$ 3,387

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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