RELATED-PARTY TRANSACTIONS - Schedule of Premiums and Losses Ceded by Company Assumed 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]
Assumed written premiums	$ 16	$ 13	$ 40	$ 27
Ceded written premiums	(88)	(115)	(294)	(231)
Assumed premiums earned	15	29	35	38
Ceded earned premiums	(118)	(115)	(234)	(231)
Assumed losses and LAE	3	3	0	(4)
Ceded losses and LAE	$ 7	$ 2	$ 5	$ 1

Amount of earned premiums ceded to other entities.

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+ Details