FAIR VALUE DISCLOSURES - UNREALIZED GAINS (LOSSES) FOR LEVEL 3 STILL HELD (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Change in Accounting Estimate [Line Items]
Investment Gains (Losses), Net	$ (9)	$ (8)	$ 73	$ (9)
Level 3 | Corporate
Change in Accounting Estimate [Line Items]
Net Derivative Gains (losses)	(4)	0	(4)	0
OCI	(1)	6	(15)	0
Level 3 | States and political subdivisions
Change in Accounting Estimate [Line Items]
Net Derivative Gains (losses)	0	0	0	0
OCI	0	0	(1)	0
Level 3 | Commercial mortgage-backed
Change in Accounting Estimate [Line Items]
Net Derivative Gains (losses)	0	(9)	0	(29)
OCI	0	8	0	27
Level 3 | Asset-backed
Change in Accounting Estimate [Line Items]
Net Derivative Gains (losses)	0	0	0	15
OCI	1	(3)	0	(10)
Level 3 | GMIB reinsurance contracts
Change in Accounting Estimate [Line Items]
Net Derivative Gains (losses)	0	0	0	0
OCI	0	0	0	0
Level 3 | Separate Accounts assets
Change in Accounting Estimate [Line Items]
Net Derivative Gains (losses)	6	4	19	22
OCI	0	$ 0	$ 0	$ 0
Level 3 | Assets and Liabilities Still Held | Corporate
Change in Accounting Estimate [Line Items]
Investment Gains (Losses), Net	0
Net Derivative Gains (losses)	0
OCI	(13)
Level 3 | Assets and Liabilities Still Held | States and political subdivisions
Change in Accounting Estimate [Line Items]
Investment Gains (Losses), Net	0
Net Derivative Gains (losses)	0
OCI	(1)
Level 3 | Assets and Liabilities Still Held | Commercial mortgage-backed
Change in Accounting Estimate [Line Items]
Investment Gains (Losses), Net	0
Net Derivative Gains (losses)	0
OCI	0
Level 3 | Assets and Liabilities Still Held | Asset-backed
Change in Accounting Estimate [Line Items]
Investment Gains (Losses), Net	0
Net Derivative Gains (losses)	0
OCI	0
Level 3 | Assets and Liabilities Still Held | Subtotal
Change in Accounting Estimate [Line Items]
Investment Gains (Losses), Net	0
Net Derivative Gains (losses)	0
OCI	(14)
Level 3 | Assets and Liabilities Still Held | GMIB reinsurance contracts
Change in Accounting Estimate [Line Items]
Investment Gains (Losses), Net	0
Net Derivative Gains (losses)	(1,488)
OCI	0
Level 3 | Assets and Liabilities Still Held | Separate Accounts assets
Change in Accounting Estimate [Line Items]
Investment Gains (Losses), Net	19
Net Derivative Gains (losses)	0
OCI	0
Level 3 | Assets and Liabilities Still Held | GMxB derivative features’ liability
Change in Accounting Estimate [Line Items]
Investment Gains (Losses), Net	0
Net Derivative Gains (losses)	394
OCI	0
Level 3 | Assets and Liabilities Still Held | Total
Change in Accounting Estimate [Line Items]
Investment Gains (Losses), Net	19
Net Derivative Gains (losses)	(1,094)
OCI	$ (14)