FAIR VALUE DISCLOSURES - Quantitative Information About Level 3 (Details) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	$ 10,007	$ 8,271
Corporate | Level 3 | Matrix pricing model
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	$ 237	$ 51
Corporate | Level 3 | Matrix pricing model | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Spread over Benchmark	0	0.0065
Corporate | Level 3 | Matrix pricing model | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Spread over Benchmark	0.058	0.058
Corporate | Level 3 | Matrix pricing model | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Spread over Benchmark	0.0034	0.0186
Corporate | Level 3 | Market comparable companies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	$ 1,062	$ 1,025
Corporate | Level 3 | EBITDA multiple | Market comparable companies | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, measurement input	3.7	3.3
Corporate | Level 3 | EBITDA multiple | Market comparable companies | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, measurement input	33.6	56.7
Corporate | Level 3 | EBITDA multiple | Market comparable companies | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, measurement input	14	14.3
Corporate | Level 3 | Discount rate | Market comparable companies | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, measurement input	0.062	0.039
Corporate | Level 3 | Discount rate | Market comparable companies | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, measurement input	0.252	0.165
Corporate | Level 3 | Discount rate | Market comparable companies | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, measurement input	0.101	0.100
Corporate | Level 3 | Cash flow multiples | Market comparable companies | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, measurement input	0.8	0.8
Corporate | Level 3 | Cash flow multiples | Market comparable companies | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, measurement input	25.8	48.1
Corporate | Level 3 | Cash flow multiples | Market comparable companies | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities, measurement input	11.1	10.7
GMIB reinsurance contracts | Level 3 | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	$ 3,433	$ 2,466
GMIB reinsurance contracts | Level 3 | Non-performance risk | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0055	0.0055
GMIB reinsurance contracts | Level 3 | Non-performance risk | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0144	0.0109
GMIB reinsurance contracts | Level 3 | Non-performance risk | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0073
GMIB reinsurance contracts | Level 3 | Lapse rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.008	0.008
GMIB reinsurance contracts | Level 3 | Lapse rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.10	0.1000
GMIB reinsurance contracts | Level 3 | Lapse rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0155
GMIB reinsurance contracts | Level 3 | Withdrawal rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0	0
GMIB reinsurance contracts | Level 3 | Withdrawal rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.08	0.080
GMIB reinsurance contracts | Level 3 | Withdrawal rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0111
GMIB reinsurance contracts | Level 3 | Utilization rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0	0
GMIB reinsurance contracts | Level 3 | Utilization rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.49	0.490
GMIB reinsurance contracts | Level 3 | Utilization rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.062
GMIB reinsurance contracts | Level 3 | Volatility rates - Equity | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.14	0.090
GMIB reinsurance contracts | Level 3 | Volatility rates - Equity | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.34	0.300
GMIB reinsurance contracts | Level 3 | Volatility rates - Equity | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.24
GMIB reinsurance contracts | Level 3 | Mortality rates | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0276
GMIBNLG | Level 3 | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Embedded Derivative, Fair Value of Embedded Derivative Liability	$ 12,081	$ 8,128
GMIBNLG | Level 3 | Non-performance risk | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0166	0.0124
GMIBNLG | Level 3 | Lapse rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.008	0.008
GMIBNLG | Level 3 | Lapse rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.199	0.199
GMIBNLG | Level 3 | Lapse rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0259
GMIBNLG | Level 3 | Withdrawal rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.003	0.003
GMIBNLG | Level 3 | Withdrawal rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.110	0.110
GMIBNLG | Level 3 | Withdrawal rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0117
GMIBNLG | Level 3 | Annuitization rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0	0
GMIBNLG | Level 3 | Annuitization rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	1.000	1.000
GMIBNLG | Level 3 | Annuitization rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0619
GMIBNLG | Level 3 | Mortality rates | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0138
GWBL/GMWB | Level 3 | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Embedded Derivative, Fair Value of Embedded Derivative Liability	$ 167	$ 109
GWBL/GMWB | Level 3 | Non-performance risk | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0166	0.0124
GWBL/GMWB | Level 3 | Lapse rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.008	0.008
GWBL/GMWB | Level 3 | Lapse rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.10	0.100
GWBL/GMWB | Level 3 | Lapse rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0155
GWBL/GMWB | Level 3 | Withdrawal rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0	0
GWBL/GMWB | Level 3 | Withdrawal rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.070	0.070
GWBL/GMWB | Level 3 | Withdrawal rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0111
GWBL/GMWB | Level 3 | Utilization rate | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	1	1
GWBL/GMWB | Level 3 | Volatility rates - Equity | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.14	0.090
GWBL/GMWB | Level 3 | Volatility rates - Equity | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.34	0.300
GWBL/GMWB | Level 3 | Volatility rates - Equity | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.2408
GIB | Level 3 | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Embedded Derivative, Fair Value of Embedded Derivative Liability	$ 124	$ 5
GIB | Level 3 | Non-performance risk | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0166
GIB | Level 3 | Lapse rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.012	0.012
GIB | Level 3 | Lapse rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.199	0.199
GIB | Level 3 | Lapse rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0155
GIB | Level 3 | Withdrawal rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0	0
GIB | Level 3 | Withdrawal rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.08	0.080
GIB | Level 3 | Withdrawal rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0111
GIB | Level 3 | Utilization rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0	0
GIB | Level 3 | Utilization rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	1	1.000
GIB | Level 3 | Utilization rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0620
GIB | Level 3 | Volatility rates - Equity | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.14	0.090
GIB | Level 3 | Volatility rates - Equity | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.34	0.300
GIB | Level 3 | Volatility rates - Equity | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.2400
GMAB | Level 3 | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Embedded Derivative, Fair Value of Embedded Derivative Liability	$ 10	$ 4
GMAB | Level 3 | Non-performance risk | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.000166
GMAB | Level 3 | Lapse rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.01	0.010
GMAB | Level 3 | Lapse rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.100	0.100
GMAB | Level 3 | Volatility rates - Equity | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.140	0.090
GMAB | Level 3 | Volatility rates - Equity | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.340	0.300
Age 0-40 | GMIB reinsurance contracts | Level 3 | Mortality rates | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0001	0.0001
Age 0-40 | GMIB reinsurance contracts | Level 3 | Mortality rates | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0018	0.0018
Age 0-40 | GMIBNLG | Level 3 | Mortality rates | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0001	0.0001
Age 0-40 | GMIBNLG | Level 3 | Mortality rates | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0019	0.0019
Age 41-60 | GMIB reinsurance contracts | Level 3 | Mortality rates | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0007	0.0007
Age 41-60 | GMIB reinsurance contracts | Level 3 | Mortality rates | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0054	0.0054
Age 41-60 | GMIBNLG | Level 3 | Mortality rates | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0006	0.0006
Age 41-60 | GMIBNLG | Level 3 | Mortality rates | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0053	0.0053
Ages 61 - 115 | GMIB reinsurance contracts | Level 3 | Mortality rates | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.0042
Ages 61 - 115 | GMIB reinsurance contracts | Level 3 | Mortality rates | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input	0.422
Ages 61 - 115 | GMIBNLG | Level 3 | Mortality rates | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.0041
Ages 61 - 115 | GMIBNLG | Level 3 | Mortality rates | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input	0.4139
Ages 60 - 115 | GMIB reinsurance contracts | Level 3 | Mortality rates | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input		0.0042
Ages 60 - 115 | GMIB reinsurance contracts | Level 3 | Mortality rates | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing asset, measurement input		0.4220
Ages 60 - 115 | GMIBNLG | Level 3 | Mortality rates | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input		0.0041
Ages 60 - 115 | GMIBNLG | Level 3 | Mortality rates | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Servicing liability, measurement input		0.414