Investments - Net Investment Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Investment income (loss) from portfolios
Total investment income	$ 44,927	$ 29,881	$ 63,426
Less: investment expenses	355	1,296	1,249
Net investment income	44,572	28,585	62,177
Available-for-sale securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	42,563	31,913	23,795
Equity securities
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	4,493	3,904	4,321
Limited partnerships
Investment income (loss) from portfolios
Limited partnerships	(11,308)	(10,446)	31,701
Cash equivalents and other
Investment income (loss) from portfolios
Available-for-sale, equity securities, cash equivalents, and other	$ 9,179	$ 4,510	$ 3,609

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

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