INVESTMENTS - Investment Gains (Losses), Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net Investment Income [Line Items]
Investment gains (losses), net	$ 787	$ 206	$ 4
Fixed maturities
Net Investment Income [Line Items]
Investment gains (losses), net	801	203	6
Mortgage loans on real estate
Net Investment Income [Line Items]
Investment gains (losses), net	(45)	(1)	0
Other equity investments
Net Investment Income [Line Items]
Investment gains (losses), net	30	3	0
Other
Net Investment Income [Line Items]
Investment gains (losses), net	$ 1	$ 1	$ (2)