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, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Effects of Reinsurance [Line Items]
Ceded written premiums	$ 75	$ 88	$ 205	$ 294
Ceded earned premiums	88	118	178	234
Mt Logan Re
Effects of Reinsurance [Line Items]
Ceded written premiums	72	63	173	209
Ceded earned premiums	72	75	173	182
Ceded losses and LAE	$ 9	$ (4)	$ 27	$ 109

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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