FAIR VALUE DISCLOSURES - Unrealized Gains (Losses) for Level 3 Instruments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Level 3 Assets And Liabilities Held
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net Derivative Gains (Losses)	$ (472)	$ (390)
OCI	(71)	14
Corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net Derivative Gains (Losses)	0	0
OCI	(61)	9
States and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net Derivative Gains (Losses)	0	0
OCI	(2)	1
Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net Derivative Gains (Losses)	0	0
OCI	(8)	4
Fixed maturities, AFS
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net Derivative Gains (Losses)	0	0
OCI	(71)	14
GMIB Reinsurance Contract Asset
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net Derivative Gains (Losses)	726	18
OCI	0	0
GMxB derivative features liability
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net Derivative Gains (Losses)	(1,198)	(408)
OCI	$ 0	$ 0