Investments - Net Investment Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Investment income (loss) from portfolios
Total investment income	$ 88,247	$ 71,795	$ 44,927
Less: investment expenses	2,410	1,640	355
Net investment income	85,837	70,155	44,572
Available-for-sale securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	57,093	49,605	42,563
Equity securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	4,637	4,758	4,493
Limited partnerships
Investment income (loss) from portfolios
Limited partnerships	3,549	1,971	(11,308)
Agent loans
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	6,417	4,368	3,236
Cash equivalents and other
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	$ 16,551	$ 11,093	$ 5,943

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