FAIR VALUE DISCLOSURES - Quantitative Information About Level 3 (Details) $ in Millions	Dec. 31, 2023 USD ($)	Apr. 01, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets for market risk benefits	$ 24	$ 8,200	$ 11
Liability for market risk benefits	7,333		16
Level 3 | Corporate | Matrix pricing model
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value, fixed maturities AFS	$ 39		$ 4
Level 3 | Corporate | Spread over benchmark | Matrix pricing model | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Percentage measurement input of equity securities	0.0095		0.0245
Level 3 | Corporate | Spread over benchmark | Matrix pricing model | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Percentage measurement input of equity securities	0.0120		0.0245
Level 3 | Corporate | Spread over benchmark | Matrix pricing model | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Percentage measurement input of equity securities	0.0118		0.0245
Level 3 | MRB | Discounted cash flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value, fixed maturities AFS	$ 9		$ 13
Fair value, liabilities	$ 7,309		$ 5
Level 3 | MRB | Non-performance Risk | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0023		0.0157
Level 3 | MRB | Non-performance Risk | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0118
Level 3 | MRB | Non-performance Risk | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0023		0.0157
Level 3 | MRB | Lapse rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0021		0.0035
Level 3 | MRB | Lapse rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.2937		0.3542
Level 3 | MRB | Lapse rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Percentage measurement input of equity securities	0.0399
Measurement input of servicing liability			0.0435
Level 3 | MRB | Withdrawal rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0000		0.0020
Level 3 | MRB | Withdrawal rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.1497		0.0124
Level 3 | MRB | Withdrawal rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0067		0.0122
Level 3 | MRB | Annuitization rate | Discounted cash flow | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0004		0.0004
Level 3 | MRB | Annuitization rate | Discounted cash flow | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	1.0000		1.0000
Level 3 | MRB | Annuitization rate | Discounted cash flow | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0304		0.0327
Level 3 | MRB | Mortality rates | Discounted cash flow | Age 0-40 | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0001		0.0001
Level 3 | MRB | Mortality rates | Discounted cash flow | Age 0-40 | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0018		0.0017
Level 3 | MRB | Mortality rates | Discounted cash flow | Age 0-40 | Weighted Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0262		0.0108
Level 3 | MRB | Mortality rates | Discounted cash flow | Age 41-60 | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0007		0.0006
Level 3 | MRB | Mortality rates | Discounted cash flow | Age 41-60 | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0053		0.0052
Level 3 | MRB | Mortality rates | Discounted cash flow | Age 61-115 | Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.0033		0.0032
Level 3 | MRB | Mortality rates | Discounted cash flow | Age 61-115 | Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Measurement input of servicing liability	0.4200		0.4000