INVESTMENTS - Schedule of Components of Net Gains (Losses) on Investments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale [Line Items]
Total net gains (losses) on investments	$ (180)	$ (982)	$ 501
Fixed maturity securities: | Market Value
Debt Securities, Available-for-Sale [Line Items]
Allowances for credit losses	(1)	(27)	(26)
Net realized gains (losses) from dispositions	(192)	(79)	8
Gains (losses) from fair value adjustments	0	0	0
Equity securities: | Fair Value
Debt Securities, Available-for-Sale [Line Items]
Net realized gains (losses) from dispositions	8	117	24
Gains (losses) from fair value adjustments	(4)	(447)	254
Other invested assets	0	13	6
Other invested assets, fair value:
Debt Securities, Available-for-Sale [Line Items]
Gains (losses) from fair value adjustments	9	(558)	234
Short-term investment gains (losses)
Debt Securities, Available-for-Sale [Line Items]
Net realized gains (losses) from dispositions	$ 0	$ 0	$ 0