INVESTMENTS - Schedule of Components of Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	$ 345	$ 321	$ 714	$ 643
Funds held interest income (expense)	(2)	1	(1)	5
Gross investment income	343	322	713	648
Investment expenses	8	8	17	15
Net investment income	335	314	696	633
Fixed maturities
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	276	267	539	532
Equity securities
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	1	1	3	2
Short-term investments
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	12	15	26	43
Limited partnerships
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	17	8	63	(1)
Dividends from preferred shares of affiliate
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	8	8	16	16
Other
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	$ 31	$ 22	$ 68	$ 52

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