INVESTMENTS - Schedule of Components of Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	$ 445,064	$ 429,441	$ 1,277,017	$ 1,242,350
Investment expenses	(6,710)	(5,582)	(20,202)	(16,871)
Net investment income	438,354	423,859	1,256,815	1,225,479
Fixed maturity investments trading
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	287,139	289,687	854,035	820,876
Short term investments
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	51,855	46,746	141,299	141,923
Fixed income exchange traded funds
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	15,876	0	23,588	0
Other equity investments
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	610	670	1,951	1,819
Catastrophe bonds
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	50,503	61,175	153,205	177,860
Other
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	27,036	20,937	67,451	59,525
Cash and cash equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	$ 12,045	$ 10,226	$ 35,488	$ 40,347

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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