POLICYHOLDER ACCOUNT BALANCES - Aggregate Fair Value of Separate Account Assets (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Policyholder Account Balance [Line Items]
Separate Accounts assets	$ 126,905	$ 121,497
Debt securities
Policyholder Account Balance [Line Items]
Separate Accounts assets	73	76
Common Stock
Policyholder Account Balance [Line Items]
Separate Accounts assets	2,262	2,213
Mutual Funds
Policyholder Account Balance [Line Items]
Separate Accounts assets	123,218	117,829
Bonds and Notes
Policyholder Account Balance [Line Items]
Separate Accounts assets	1,352	1,379
Life Insurance & Employee Benefits Products
Policyholder Account Balance [Line Items]
Separate Accounts assets	14,751	13,761
Life Insurance & Employee Benefits Products | Debt securities
Policyholder Account Balance [Line Items]
Separate Accounts assets	46	48
Life Insurance & Employee Benefits Products | Common Stock
Policyholder Account Balance [Line Items]
Separate Accounts assets	64	65
Life Insurance & Employee Benefits Products | Mutual Funds
Policyholder Account Balance [Line Items]
Separate Accounts assets	14,550	13,557
Life Insurance & Employee Benefits Products | Bonds and Notes
Policyholder Account Balance [Line Items]
Separate Accounts assets	91	91
Individual Variable Annuity Products
Policyholder Account Balance [Line Items]
Separate Accounts assets	72,834	70,854
Individual Variable Annuity Products | Debt securities
Policyholder Account Balance [Line Items]
Separate Accounts assets	1	1
Individual Variable Annuity Products | Common Stock
Policyholder Account Balance [Line Items]
Separate Accounts assets	35	34
Individual Variable Annuity Products | Mutual Funds
Policyholder Account Balance [Line Items]
Separate Accounts assets	72,795	70,815
Individual Variable Annuity Products | Bonds and Notes
Policyholder Account Balance [Line Items]
Separate Accounts assets	3	4
Employer - Sponsored Products
Policyholder Account Balance [Line Items]
Separate Accounts assets	35,668	33,249
Employer - Sponsored Products | Debt securities
Policyholder Account Balance [Line Items]
Separate Accounts assets	20	21
Employer - Sponsored Products | Common Stock
Policyholder Account Balance [Line Items]
Separate Accounts assets	450	447
Employer - Sponsored Products | Mutual Funds
Policyholder Account Balance [Line Items]
Separate Accounts assets	35,197	32,780
Employer - Sponsored Products | Bonds and Notes
Policyholder Account Balance [Line Items]
Separate Accounts assets	1	1
Other
Policyholder Account Balance [Line Items]
Separate Accounts assets	3,652	3,633
Other | Debt securities
Policyholder Account Balance [Line Items]
Separate Accounts assets	6	6
Other | Common Stock
Policyholder Account Balance [Line Items]
Separate Accounts assets	1,713	1,667
Other | Mutual Funds
Policyholder Account Balance [Line Items]
Separate Accounts assets	676	677
Other | Bonds and Notes
Policyholder Account Balance [Line Items]
Separate Accounts assets	$ 1,257	$ 1,283