INVESTMENTS - Schedule of Components of Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	$ 439,822	$ 419,704	$ 867,297	$ 831,953
Investment expenses	(7,333)	(6,596)	(14,306)	(13,492)
Net investment income	432,489	413,108	852,991	818,461
Fixed maturity investments trading
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	297,222	282,173	591,716	566,896
Short term investments
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	32,957	48,415	67,263	89,444
Fixed income exchange traded funds
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	26,119	6,528	47,811	7,712
Common stock
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	676	615	1,353	1,341
Catastrophe bonds
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	40,095	47,948	80,027	102,702
Fund and direct private equity investments
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	33,333	21,692	58,544	40,415
Cash and cash equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Investment income before investment expenses	$ 9,420	$ 12,333	$ 20,583	$ 23,443

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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