FAIR VALUE DISCLOSURES - Level 3 Unobservable Input Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net	$ (12)	$ (5)	$ (20)	$ 82
Transfers into level 3			14	65
Transfers out of Level 3			(73)	(28)
Corporate
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net			0	0
Investment gains (losses), net			0	0
Other comprehensive income (loss)			10	(7)
Corporate | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	1,169	1,229	1,174	1,139
Total gains (losses), realized and unrealized, included in:
Investment Income, Net	2	3	3	5
Investment gains (losses), net	0	0	0	0
Subtotal	2	3	3	5
Other comprehensive income (loss)	1	6	10	(14)
Purchases	151	27	221	200
Sales	(26)	(99)	(59)	(215)
Transfers into level 3	(3)	(2)	14	65
Transfers out of Level 3	(4)	(12)	(73)	(28)
Closing Balance	1,290	1,152	1,290	1,152
Asset- backed
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net			0	0
Investment gains (losses), net			0	0
Other comprehensive income (loss)			5	(1)
Asset- backed | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	534	7	519	8
Total gains (losses), realized and unrealized, included in:
Investment Income, Net	0	0	0	0
Investment gains (losses), net	0	0	0	0
Subtotal	0	0	0	0
Other comprehensive income (loss)	1	(1)	5	(1)
Purchases	(1)	533	10	533
Sales	0	(1)	0	(2)
Transfers into level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Closing Balance	534	538	534	538
State and Political Sub-divisions
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net			0	0
Investment gains (losses), net			0	0
Other comprehensive income (loss)			2	(1)
State and Political Sub-divisions | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	39	39	38	40
Total gains (losses), realized and unrealized, included in:
Investment Income, Net	0	0	0	0
Investment gains (losses), net	0	0	0	0
Subtotal	0	0	0	0
Other comprehensive income (loss)	1	0	2	(1)
Purchases	0	0	0	0
Sales	(1)	(1)	(1)	(1)
Transfers into level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Closing Balance	39	38	39	38
Other Equity Investments | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	18	31	48	25
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net	0	0	0	0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value Nonperformance Risk	0	0	0	0
Subtotal	0	0	0	0
Other comprehensive income (loss)	0	0	0	0
Purchases	0	0	0	0
Sales	0	0	0	0
Settlements	0	0	0	0
Activity related to consolidated VIEs	(2)	(3)	(3)	(2)
Transfers into level 3	0	0	0	5
Transfers out of Level 3	0	(5)	(29)	(5)
Closing Balance	16	23	16	23
Fair Value Assets Measured On Recurring Basis Gain Loss Included In Reinsurance Contracts	0	0	0	0
GMIB Reinsurance Asset
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net			0	0
Investment gains (losses), net			217	(1,233)
Other comprehensive income (loss)			0	0
GMIB Reinsurance Asset | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	2,009	9,674	1,991	10,488
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net	0	0	0	0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value Nonperformance Risk	12	(1)	52	(57)
Subtotal	190	(392)	217	(1,233)
Other comprehensive income (loss)	0	0	0	0
Purchases	11	17	23	71
Sales	(14)	(11)	(35)	(38)
Settlements	0	(7,463)	0	(7,463)
Activity related to consolidated VIEs	0	0	0	0
Transfers into level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Closing Balance	2,196	1,825	2,196	1,825
Fair Value Assets Measured On Recurring Basis Gain Loss Included In Reinsurance Contracts	178	(391)	165	(1,176)
Separate Accounts Assets
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net			5	14
Investment gains (losses), net			0	0
Other comprehensive income (loss)			0	0
Separate Accounts Assets | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	383	357	374	349
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net	5	7	12	14
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value Nonperformance Risk	0	0	0	0
Subtotal	5	7	12	14
Other comprehensive income (loss)	0	0	0	0
Purchases	3	(1)	7	2
Sales	0	0	0	(1)
Settlements	(2)	(2)	(3)	(3)
Activity related to consolidated VIEs	0	0	0	0
Transfers into level 3	0	0	0	0
Transfers out of Level 3	0	0	(1)	0
Closing Balance	389	361	389	361
Fair Value Assets Measured On Recurring Basis Gain Loss Included In Reinsurance Contracts	0	0	0	0
GMxB derivative features liability
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net			0	0
Investment gains (losses), net			(1,116)	928
Other comprehensive income (loss)			0	0
Guaranteed Income Benefit Guaranteed Withdrawal Benefit And Other Features Liability [Member] | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance	(5,944)	(3,862)	(5,431)	(4,256)
Total gains (losses), realized and unrealized, included in:
Investment gains (losses), net	0	0	0	0
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value Nonperformance Risk	0	72	(460)	121
Subtotal	(707)	443	(1,116)	928
Other comprehensive income (loss)	0	0	0	0
Purchases	(103)	(116)	(210)	(209)
Sales	5	1	8	3
Settlements	0	0	0	0
Activity related to consolidated VIEs	0	0	0	0
Transfers into level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Closing Balance	(6,749)	(3,534)	(6,749)	(3,534)
Fair Value Assets Measured On Recurring Basis Gain Loss Included In Reinsurance Contracts	$ (707)	$ 371	$ (656)	$ 807