FAIR VALUE DISCLOSURES - Level 3 Unobservable Input Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Total gains (losses), realized and unrealized, included in:
Transfers into level 3	$ 17	$ 67
Transfers out of Level 3	(69)	(16)
Corporate | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	1,174	1,139
Total gains (losses), realized and unrealized, included in:
Investment Income, Net	1
Net investment income (loss)		2
Other comprehensive income (loss)	9	(20)
Purchases	70	173
Sales	(33)	116
Transfers into level 3	17	67
Transfers out of Level 3	(69)	16
Closing Balance	1,169	1,229
Asset- backed | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	519	8
Total gains (losses), realized and unrealized, included in:
Investment Income, Net	0
Net investment income (loss)		0
Other comprehensive income (loss)	4	0
Purchases	11	0
Sales	0	1
Transfers into level 3	0	0
Transfers out of Level 3	0	0
Closing Balance	534	7
State and Political Sub-divisions | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	38	40
Total gains (losses), realized and unrealized, included in:
Investment Income, Net	0
Net investment income (loss)		0
Other comprehensive income (loss)	1	(1)
Purchases	0	0
Sales	0	0
Transfers into level 3	0	0
Transfers out of Level 3	0	0
Closing Balance	39	39
Other Equity Investments | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	48	25
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net	0	0
Net derivative gains (losses)	0	0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value Nonperformance Risk	0	0
Subtotal	0	0
Purchases	0	0
Sales	0	0
Settlements	0	0
Activity related to consolidated VIEs	(1)	1
Transfers into level 3		5
Transfers out of Level 3	(29)
Closing Balance	18	31
GMIB Reinsurance Asset | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	1,991	10,488
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net	0	0
Net derivative gains (losses)	(13)	(854)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value Nonperformance Risk	40	13
Subtotal	27	(841)
Purchases	12	54
Sales	(21)	27
Settlements	0	0
Activity related to consolidated VIEs	0	0
Transfers into level 3		0
Transfers out of Level 3	0
Closing Balance	2,009	9,674
Separate Accounts Assets | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	374	349
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net	7	7
Net derivative gains (losses)	0	0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value Nonperformance Risk	0	0
Subtotal	7	7
Purchases	4	3
Sales	0	1
Settlements	(1)	1
Activity related to consolidated VIEs	0	0
Transfers into level 3		0
Transfers out of Level 3	(1)
Closing Balance	383	357
GMxB derivative features liability | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	(5,431)
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net	0
Net derivative gains (losses)	51
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value Nonperformance Risk	(460)
Subtotal	(409)
Purchases	(107)
Sales	3
Settlements	0
Activity related to consolidated VIEs	0
Transfers out of Level 3	0
GMxB Derivative Features Liability | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance		(4,256)
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net		0
Net derivative gains (losses)		436
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value Nonperformance Risk		49
Subtotal		485
Purchases		(93)
Sales		(2)
Settlements		0
Activity related to consolidated VIEs		0
Transfers into level 3		0
Closing Balance	$ (5,944)	$ (3,862)