INVESTMENTS - Schedule of Net Investment Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Net Investment Income [Line Items]
Investment income before investment expenses	$ 1,730,861	$ 1,677,804	$ 1,276,012
Investment expenses	(27,386)	(23,515)	(22,902)
Net investment income	1,703,475	1,654,289	1,253,110
Fixed maturity investments trading
Net Investment Income [Line Items]
Investment income before investment expenses	1,144,271	1,116,649	744,457
Short term investments
Net Investment Income [Line Items]
Investment income before investment expenses	190,549	183,153	213,303
Fixed income exchange traded funds
Net Investment Income [Line Items]
Investment income before investment expenses	48,897	0	4,306
Common Stock
Net Investment Income [Line Items]
Investment income before investment expenses	2,671	2,460	2,955
Catastrophe bonds
Net Investment Income [Line Items]
Investment income before investment expenses	200,465	238,844	200,572
Fund and direct private equity investments
Net Investment Income [Line Items]
Investment income before investment expenses	96,629	82,457	87,296
Cash and cash equivalents
Net Investment Income [Line Items]
Investment income before investment expenses	$ 47,379	$ 54,241	$ 23,123

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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