DERIVATIVE INSTRUMENTS - Schedule of Interest Rate Fair Value Hedges Hedged Items (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount		$ 53,291	$ 61,695
Fair value hedges
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount		9,115	12,780
Interest rate swaptions | Fair value hedges
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount		243	243
Fixed maturity securities | Interest rate swaptions
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Carrying Amount of Hedged Assets/ (Liabilities)	[1]	4,469	4,633
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Assets/(Liabilities)		$ 249	$ 256

[1] The balance includes hedging adjustment on discontinued hedging relationships of $249 in 2020 and $256 in 2019.