INVESTMENTS - Schedule of Components of Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	$ 321	$ 360	$ 643	$ 679
Funds held interest income (expense)	1	1	5	5
Gross investment income	322	361	648	684
Investment expenses	8	13	15	24
Net investment income	314	348	633	660
Fixed maturities
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	267	255	532	500
Equity securities
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	1	1	2	2
Short-term investments and cash
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	15	22	43	44
Limited partnerships
Debt Securities, Available-for-Sale [Line Items]
Gross investment income before adjustments	8	44	(1)	68
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	$ 22	$ 30	$ 52	$ 50

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