Investments - Schedule of Net Investment Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net Investment Income [Line Items]
Gross investment income	$ 1,276,012	$ 581,549	$ 340,229
Investment expenses	(22,902)	(21,617)	(20,750)
Net investment income	1,253,110	559,932	319,479
Fixed maturity investments trading
Net Investment Income [Line Items]
Gross investment income	744,457	382,165	234,911
Short term investments
Net Investment Income [Line Items]
Gross investment income	213,303	41,042	2,333
Equity investments
Net Investment Income [Line Items]
Gross investment income	7,261	20,864	9,017
Catastrophe bonds
Net Investment Income [Line Items]
Gross investment income	200,572	94,784	64,860
Other
Net Investment Income [Line Items]
Gross investment income	87,296	37,497	28,811
Cash and cash equivalents
Net Investment Income [Line Items]
Gross investment income	$ 23,123	$ 5,197	$ 297

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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