REINSURANCE - Schedule of Effect of Reinsurance and Retrocessional Activity on Premiums Written and Earned and on Net Claims and Claim Expenses Incurred (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Premiums Written
Direct	$ 243,656	$ 320,657
Assumed	3,911,847	3,670,027
Ceded	(711,974)	(791,111)
Net premiums written	3,443,529	3,199,573
Premiums Earned
Direct	251,894	279,742
Assumed	2,855,327	2,597,198
Ceded	(386,440)	(433,030)
Net premiums earned (Note 5)	2,720,781	2,443,910
Claims and Claim Expenses
Gross claims and claim expenses incurred	3,104,842	1,159,623
Claims and claim expenses recovered	(361,084)	6,500
Net claims and claim expenses incurred	$ 2,743,758	$ 1,166,123

Amount of earned premiums assumed from other entities.

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Amount of written premiums ceded to other entities.

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Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums written.

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Amount, before effect of policies assumed or ceded, of expense related to provision for policy benefits and costs incurred.

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Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred.

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums written.

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Amount of recovery (expense) related to provision for policy benefits and costs incurred for policies assumed and ceded.

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