FAIR VALUE OF ASSETS AND LIABILITIES - Quantitative Information Regarding Internally-Prices Level 3 Assets and Liabilities (Details) $ in Millions	3 Months Ended
	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Assets
Debt securities, available-for-sale	$ 5,239	$ 5,024
Deposit asset	608	607
Net modified coinsurance receivable	0	18
Liabilities:
Insurance liabilities, at fair value	5,751	5,546
Net modified coinsurance payable	45	0
Retained Business
Assets
Net modified coinsurance receivable		0
Liabilities:
Insurance liabilities, at fair value	3,056	2,941
Ceded Business
Assets
Net modified coinsurance receivable		18
Liabilities:
Insurance liabilities, at fair value	$ 2,695	$ 2,605
Level 3 | Minimum
Liabilities:
Policyholder age	45 years
Level 3 | Minimum | Mortality rate
Liabilities:
Insurance liability, measurement input	0
Level 3 | Maximum
Liabilities:
Policyholder age	90 years
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Equality volatility curve | Retained Business
Liabilities:
Insurance liability, measurement input	0.195	0.195
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Equality volatility curve | Ceded Business
Liabilities:
Insurance liability, measurement input	0.195	0.195
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Lapse rate | Retained Business
Liabilities:
Insurance liability, measurement input	0.01	0.01
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Lapse rate | Ceded Business
Liabilities:
Insurance liability, measurement input	0.01	0.01
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Spread over risk free | Retained Business
Liabilities:
Insurance liability, measurement input	0.0000	0.0000
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Spread over risk free | Ceded Business
Liabilities:
Insurance liability, measurement input	0.0000	0.0000
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Utilization rate | Retained Business
Liabilities:
Insurance liability, measurement input	0.77	0.925
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Utilization rate | Ceded Business
Liabilities:
Insurance liability, measurement input	0.77	0.925
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Mortality rate | Retained Business
Liabilities:
Insurance liability, measurement input	0	0
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Mortality rate | Ceded Business
Liabilities:
Insurance liability, measurement input	0	0
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Corporate Securities | Discount rate
Assets
Debt securities, measurement input	0.0488	0.0475
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Foreign corporate public securities | Discount rate
Assets
Debt securities, measurement input	0.0434	0.0433
Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Asset-backed securities | Discount rate
Assets
Debt securities, measurement input	0.0683	0.0719
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Equality volatility curve | Retained Business
Liabilities:
Insurance liability, measurement input	0.26	0.26
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Equality volatility curve | Ceded Business
Liabilities:
Insurance liability, measurement input	0.26	0.26
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Lapse rate | Retained Business
Liabilities:
Insurance liability, measurement input	0.20	0.20
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Lapse rate | Ceded Business
Liabilities:
Insurance liability, measurement input	0.20	0.20
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Spread over risk free | Retained Business
Liabilities:
Insurance liability, measurement input	0.0248	0.0243
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Spread over risk free | Ceded Business
Liabilities:
Insurance liability, measurement input	0.0207	0.0221
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Utilization rate | Retained Business
Liabilities:
Insurance liability, measurement input	1	1
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Utilization rate | Ceded Business
Liabilities:
Insurance liability, measurement input	1	1
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Mortality rate | Retained Business
Liabilities:
Insurance liability, measurement input	0.16	0.16
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Mortality rate | Ceded Business
Liabilities:
Insurance liability, measurement input	0.16	0.16
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Corporate Securities | Discount rate
Assets
Debt securities, measurement input	0.0919	0.0803
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Foreign corporate public securities | Discount rate
Assets
Debt securities, measurement input	0.0642	0.0638
Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Asset-backed securities | Discount rate
Assets
Debt securities, measurement input	0.0864	0.0851
Level 3 | Valuation Technique, Discounted Cash Flow | Weighted Average | Corporate Securities | Discount rate
Assets
Debt securities, measurement input	0.0665	0.0656
Level 3 | Valuation Technique, Discounted Cash Flow | Weighted Average | Foreign corporate public securities | Discount rate
Assets
Debt securities, measurement input	0.0538	0.0536
Level 3 | Valuation Technique, Discounted Cash Flow | Weighted Average | Asset-backed securities | Discount rate
Assets
Debt securities, measurement input	0.0805	0.0794
Level 3 | Valuation Technique, Level Yield | Minimum | Residential mortgage loans | Market yield
Assets
Loans receivable, measurement input	0.0676	0.0575
Level 3 | Valuation Technique, Level Yield | Maximum  | Residential mortgage loans | Market yield
Assets
Loans receivable, measurement input	0.1003	0.0997
Level 3 | Valuation Technique, Level Yield | Weighted Average | Residential mortgage loans | Market yield
Assets
Loans receivable, measurement input	0.0847	0.0840
Recurring
Assets
Debt securities, available-for-sale	$ 5,239	$ 5,024
Mortgage and other loans	206	196
Deposit asset	608	607
Liabilities:
Insurance liabilities, at fair value	5,751	5,546
Net modified coinsurance payable	45
Recurring | Retained Business
Assets
Debt securities, available-for-sale	3,814	3,616
Mortgage and other loans	206	196
Liabilities:
Insurance liabilities, at fair value	3,056	2,941
Recurring | Ceded Business
Assets
Debt securities, available-for-sale	1,425	1,408
Deposit asset	608	607
Liabilities:
Insurance liabilities, at fair value	2,695	2,605
Recurring | Foreign corporate public securities
Assets
Debt securities, available-for-sale	217	211
Recurring | Foreign corporate public securities | Retained Business
Assets
Debt securities, available-for-sale	127	122
Recurring | Foreign corporate public securities | Ceded Business
Assets
Debt securities, available-for-sale	90	89
Recurring | Asset-backed securities
Assets
Debt securities, available-for-sale	669	532
Recurring | Asset-backed securities | Retained Business
Assets
Debt securities, available-for-sale	650	513
Recurring | Asset-backed securities | Ceded Business
Assets
Debt securities, available-for-sale	19	19
Recurring | Commercial mortgage-backed securities
Assets
Debt securities, available-for-sale	42	43
Recurring | Commercial mortgage-backed securities | Retained Business
Assets
Debt securities, available-for-sale	42	43
Recurring | Commercial mortgage-backed securities | Ceded Business
Assets
Debt securities, available-for-sale		0
Recurring | Level 3
Assets
Debt securities, available-for-sale	409	337
Mortgage and other loans	206	196
Deposit asset	608	607
Net modified coinsurance receivable		18
Liabilities:
Insurance liabilities, at fair value	5,751	5,546
Net modified coinsurance payable	45
Recurring | Level 3 | Retained Business
Assets
Debt securities, available-for-sale	409	337
Mortgage and other loans	206	196
Liabilities:
Insurance liabilities, at fair value	3,056	2,941
Recurring | Level 3 | Ceded Business
Assets
Debt securities, available-for-sale	0	0
Deposit asset	608	607
Liabilities:
Insurance liabilities, at fair value	2,695	2,605
Recurring | Level 3 | Corporate Securities
Assets
Debt securities, available-for-sale	182
Recurring | Level 3 | Foreign corporate public securities
Assets
Debt securities, available-for-sale	0	0
Recurring | Level 3 | Foreign corporate public securities | Retained Business
Assets
Debt securities, available-for-sale	0	0
Recurring | Level 3 | Foreign corporate public securities | Ceded Business
Assets
Debt securities, available-for-sale	0	0
Recurring | Level 3 | Asset-backed securities
Assets
Debt securities, available-for-sale	191	155
Recurring | Level 3 | Asset-backed securities | Retained Business
Assets
Debt securities, available-for-sale	191	155
Recurring | Level 3 | Asset-backed securities | Ceded Business
Assets
Debt securities, available-for-sale	0	0
Recurring | Level 3 | Commercial mortgage-backed securities
Assets
Debt securities, available-for-sale	0	0
Recurring | Level 3 | Commercial mortgage-backed securities | Retained Business
Assets
Debt securities, available-for-sale	0	0
Recurring | Level 3 | Commercial mortgage-backed securities | Ceded Business
Assets
Debt securities, available-for-sale		0
Recurring | Level 3 | Reinsurance recoverables
Assets
Reinsurance recoverables	247	235
Recurring | Level 3 | Policyholders' account balances
Liabilities:
Net modified coinsurance payable	45
Recurring | Level 3 | Valuation, market approach | Corporate Securities
Assets
Debt securities, available-for-sale	28
Recurring | Level 3 | Valuation, market approach | Asset-backed securities
Assets
Debt securities, available-for-sale	112
Recurring | Level 3 | Valuation, market approach | Commercial mortgage-backed securities
Assets
Mortgage and other loans	48	35
Recurring | Level 3 | Valuation Technique, Discounted Cash Flow | Retained Business
Liabilities:
Insurance liabilities, at fair value	3,056	2,941
Recurring | Level 3 | Valuation Technique, Discounted Cash Flow | Ceded Business
Liabilities:
Insurance liabilities, at fair value	2,695	2,605
Recurring | Level 3 | Valuation Technique, Discounted Cash Flow | Corporate Securities
Assets
Debt securities, available-for-sale	154	146
Recurring | Level 3 | Valuation Technique, Discounted Cash Flow | Foreign corporate public securities
Assets
Debt securities, available-for-sale	36	36
Recurring | Level 3 | Valuation Technique, Discounted Cash Flow | Asset-backed securities
Assets
Debt securities, available-for-sale	$ 79	$ 155
Recurring | Level 3 | Valuation Technique, Discounted Cash Flow | Minimum | Measurement Input, Withdrawal Rate
Liabilities:
Insurance liability, measurement input	0.77	0.77
Recurring | Level 3 | Valuation Technique, Discounted Cash Flow | Maximum  | Measurement Input, Withdrawal Rate
Liabilities:
Insurance liability, measurement input	1	1
Recurring | Level 3 | Valuation Technique, Level Yield | Residential mortgage loans
Assets
Mortgage and other loans	$ 158	$ 161