INVESTMENTS - Schedule of Components of Net Gains (Losses) on Investments (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]
Credit allowance on fixed maturity securities	$ (11)	$ (2)	$ 2	$ (2)
Total net realized gains (losses) from dispositions	1	0	(12)	(2)
Net gains (losses) on investments	(8)	(2)	(38)	93
Equity securities
Debt Securities, Available-for-Sale [Line Items]
Gains (losses) from fair value adjustments:	4	4	(2)	3
Net realized gains (losses) from dispositions:	0	0	0	0
Other invested assets
Debt Securities, Available-for-Sale [Line Items]
Gains (losses) from fair value adjustments:	(2)	(4)	(26)	95
Net realized gains (losses) from dispositions:	0	0	0	0
Fixed maturities
Debt Securities, Available-for-Sale [Line Items]
Net realized gains (losses) from dispositions:	1	0	(12)	(2)
Short-term investments
Debt Securities, Available-for-Sale [Line Items]
Net realized gains (losses) from dispositions:	$ 0	$ 0	$ 0	$ 0

Investments, Allowance For (Reversal Of) Credit Loss

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