Fair Value of Financial Instruments - Fair Value of Assets and Liabilities on a Recurring Basis (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	$ 276,123	$ 263,539
Liabilities	(20,974)	(16,827)
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	836	822
Liabilities	0	0
Significant Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	259,340	248,140
Liabilities	(5,800)	(4,299)
Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	15,947	14,577
Liabilities	(15,174)	(12,528)
Corporate bonds | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	63,290	63,866
Corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Corporate bonds | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	56,543	57,397
Corporate bonds | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	6,747	6,469
U.S. government bonds | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	391	393
U.S. government bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	371	373
U.S. government bonds | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	20	20
U.S. government bonds | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
State and municipal bonds | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	2,493	2,542
State and municipal bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
State and municipal bonds | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	2,493	2,537
State and municipal bonds | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	5
Foreign government bonds | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	260	278
Foreign government bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Foreign government bonds | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	260	278
Foreign government bonds | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
RMBS | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	1,593	1,602
RMBS | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
RMBS | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	1,581	1,589
RMBS | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	12	13
CMBS | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	1,403	1,344
CMBS | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
CMBS | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	1,395	1,336
CMBS | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	8	8
ABS | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	12,222	12,043
ABS | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
ABS | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	10,530	10,559
ABS | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	1,692	1,484
Hybrid and redeemable preferred securities | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	228	232
Hybrid and redeemable preferred securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	48	46
Hybrid and redeemable preferred securities | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	129	138
Hybrid and redeemable preferred securities | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	51	48
Trading securities | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	2,203	2,321
Trading securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Trading securities | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	1,932	2,037
Trading securities | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	271	284
Equity securities | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	319	306
Equity securities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	11	1
Equity securities | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	269	263
Equity securities | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	39	42
Mortgage loans on real estate | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	289	288
Mortgage loans on real estate | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Mortgage loans on real estate | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Mortgage loans on real estate | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	289	288
Derivative investments | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	15,072	11,327
Derivative investments | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Derivative investments | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	14,345	10,705
Derivative investments | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	727	622
Other investments – short-term investments | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	217	233
Other investments – short-term investments | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Other investments – short-term investments | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	217	233
Other investments – short-term investments | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Cash and invested cash | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	3,807	3,193
Cash and invested cash | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Cash and invested cash | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	3,807	3,193
Cash and invested cash | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
MRB assets | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	4,878	3,894
MRB assets | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
MRB assets | Significant Observable Inputs (Level 2) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
MRB assets | Significant Unobservable Inputs (Level 3) | Fixed maturity AFS securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	4,878	3,894
Ceded MRBs | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	59	274
Ceded MRBs | Other liabilities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	(2,261)	(1,149)
Ceded MRBs | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Ceded MRBs | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other liabilities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	0	0
Ceded MRBs | Significant Observable Inputs (Level 2) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Ceded MRBs | Significant Observable Inputs (Level 2) | Other liabilities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	0	0
Ceded MRBs | Significant Unobservable Inputs (Level 3) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	59	274
Ceded MRBs | Significant Unobservable Inputs (Level 3) | Other liabilities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	(2,261)	(1,149)
Indexed annuity ceded embedded derivatives | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	973	940
Indexed annuity ceded embedded derivatives | Policyholder account balances
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	(10,896)	(9,077)
Indexed annuity ceded embedded derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Indexed annuity ceded embedded derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1) | Policyholder account balances
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	0	0
Indexed annuity ceded embedded derivatives | Significant Observable Inputs (Level 2) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Indexed annuity ceded embedded derivatives | Significant Observable Inputs (Level 2) | Policyholder account balances
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	0	0
Indexed annuity ceded embedded derivatives | Significant Unobservable Inputs (Level 3) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	973	940
Indexed annuity ceded embedded derivatives | Significant Unobservable Inputs (Level 3) | Policyholder account balances
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	(10,896)	(9,077)
LPR ceded derivative | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	201	206
LPR ceded derivative | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
LPR ceded derivative | Significant Observable Inputs (Level 2) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
LPR ceded derivative | Significant Unobservable Inputs (Level 3) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	201	206
Separate account assets | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	166,225	158,257
Separate account assets | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	406	402
Separate account assets | Significant Observable Inputs (Level 2) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	165,819	157,855
Separate account assets | Significant Unobservable Inputs (Level 3) | Other assets
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Assets	0	0
Reinsurance-related embedded derivatives
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	543	493
Reinsurance-related embedded derivatives | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	0	0
Reinsurance-related embedded derivatives | Significant Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	568	493
Reinsurance-related embedded derivatives | Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	(25)	0
MRB liabilities | Policyholder account balances
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	(1,266)	(1,716)
MRB liabilities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Policyholder account balances
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	0	0
MRB liabilities | Significant Observable Inputs (Level 2) | Policyholder account balances
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	0	0
MRB liabilities | Significant Unobservable Inputs (Level 3) | Policyholder account balances
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	(1,266)	(1,716)
Derivative liabilities | Other liabilities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	(7,094)	(5,378)
Derivative liabilities | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other liabilities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	0	0
Derivative liabilities | Significant Observable Inputs (Level 2) | Other liabilities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	(6,368)	(4,792)
Derivative liabilities | Significant Unobservable Inputs (Level 3) | Other liabilities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Liabilities	$ (726)	$ (586)