INVESTMENTS - Schedule of Components of Net Gains (Losses) on Investments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Total net gains (losses) on investments	$ (8)	$ 22
Fixed maturity securities \| Market Value
Debt Securities, Available-for-Sale [Line Items]
Allowances for credit losses	1	(10)
Net realized gains (losses) from dispositions	(5)	(1)
Equity securities, fair value \| Fair Value
Debt Securities, Available-for-Sale [Line Items]
Net realized gains (losses) from dispositions	1	7
Gains (losses) from fair value adjustments	(1)	3
Other invested assets	0	0
Other invested assets, fair value
Debt Securities, Available-for-Sale [Line Items]
Gains (losses) from fair value adjustments	(3)	24
Short-term investments and cash
Debt Securities, Available-for-Sale [Line Items]
Net realized gains (losses) from dispositions	$ 0	$ 0

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