RELATED-PARTY TRANSACTIONS - Schedule of Premiums and Losses Ceded by Company to Affiliate (Details) - Affiliated Entity - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Effects of Reinsurance [Line Items]
Ceded written premiums	$ 88	$ 115	$ 294	$ 231
Ceded earned premiums	118	115	234	231
Mt Logan Re
Effects of Reinsurance [Line Items]
Ceded written premiums	63	65	209	136
Ceded earned premiums	75	76	182	147
Ceded losses and LAE	$ (4)	$ 12	$ 109	$ 31

Amount of earned premiums ceded to other entities.

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+ Details