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, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Effects of Reinsurance [Line Items]
Assumed written premiums	$ 15	$ 16	$ 39	$ 40
Ceded written premiums	(75)	(88)	(205)	(294)
Assumed premiums earned	14	15	43	35
Ceded earned premiums	(88)	(118)	(178)	(234)
Assumed losses and LAE	8	3	16	0
Ceded losses and LAE	$ (1)	$ 7	$ (1)	$ 5

Amount of earned premiums ceded to other entities.

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+ Details

- Definition

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.

+ References

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+ Details