INVESTMENTS - Schedule of Components of Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	$ 419,704	$ 417,373	$ 831,953	$ 812,909
Investment expenses	(6,596)	(6,528)	(13,492)	(11,289)
Net investment income	413,108	410,845	818,461	801,620
Fixed maturity investments trading
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	282,173	273,900	566,896	531,189
Short term investments
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	48,415	48,386	89,444	95,177
Fixed income exchange traded funds
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	6,528	0	7,712	0
Other equity investments
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	615	589	1,341	1,149
Catastrophe bonds
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	47,948	58,436	102,702	116,685
Other
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	21,692	20,663	40,415	38,588
Cash and cash equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	$ 12,333	$ 15,399	$ 23,443	$ 30,121

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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