Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Components of net investment income
Gross investment income	$ 47,073	$ 31,289	$ 92,268	$ 57,556
Investment expenses	(1,823)	(1,950)	(3,782)	(3,537)
Net investment income	45,250	29,339	88,486	54,019
Fixed maturities
Components of net investment income
Gross investment income	43,775	31,074	87,251	57,298
Short-term investments
Components of net investment income
Gross investment income	$ 3,298	$ 215	$ 5,017	$ 258

Amount, before 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. Excludes realized gain (loss) on investments.

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Amount of expenses related to the generation of investment income.

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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. Excludes realized gain (loss) on investments.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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