Fair Value of Financial Instruments - Carrying Amounts of Assets and Liabilities at Estimated Fair Value Measured on a Recurring Basis (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Assets
Fixed maturity securities available for sale	$ 44,566	$ 42,373
Derivative asset	1,024	797
Market risk benefits asset	95	88
Total financial assets at fair value	1,338	1,312
Derivatives:
Market risk benefits liability	425	403
Level 1
Assets
Cash and cash equivalents	3,517	2,767
Short term investments	637	2,111
Derivative asset	0	0
Investment in unconsolidated affiliates	0	0
Market risk benefits asset	0	0
Total financial assets at fair value	5,872	6,566
Derivatives:
Contingent consideration obligation	0
Market risk benefits liability	0	0
Total financial liabilities at fair value	3	1
Level 2
Assets
Cash and cash equivalents	0	0
Short term investments	0	8
Derivative asset	1,015	740
Investment in unconsolidated affiliates	0	0
Market risk benefits asset	0	0
Total financial assets at fair value	35,292	33,703
Derivatives:
Contingent consideration obligation	0
Market risk benefits liability	0	0
Total financial liabilities at fair value	0	0
Level 3
Assets
Cash and cash equivalents	0	0
Short term investments	9	0
Derivative asset	9	57
Investment in unconsolidated affiliates	343	285
Market risk benefits asset	95	88
Total financial assets at fair value	10,476	9,677
Derivatives:
Contingent consideration obligation	57
Market risk benefits liability	425	403
Total financial liabilities at fair value	5,180	4,661
NAV
Assets
Total financial assets at fair value	59	59
Fair Value
Assets
Cash and cash equivalents	3,517	2,767
Short term investments	646	2,119
Derivative asset	1,024	797
Investment in unconsolidated affiliates	343	285
Market risk benefits asset	95	88
Total financial assets at fair value	51,699	50,005
Derivatives:
Contingent consideration obligation	57
Market risk benefits liability	425	403
Total financial liabilities at fair value	5,183	4,662
Reinsurance related embedded derivative, included in other assets \| Level 1
Assets
Derivative asset	0	0
Reinsurance related embedded derivative, included in other assets \| Level 2
Assets
Derivative asset	134	152
Reinsurance related embedded derivative, included in other assets \| Level 3
Assets
Derivative asset	0	0
Reinsurance related embedded derivative, included in other assets \| Fair Value
Assets
Derivative asset	134	152
Indexed annuities/IUL embedded derivatives, included in contractholder funds \| Level 1
Derivatives:
Derivative liability	0	0
Indexed annuities/IUL embedded derivatives, included in contractholder funds \| Level 2
Derivatives:
Derivative liability	0	0
Indexed annuities/IUL embedded derivatives, included in contractholder funds \| Level 3
Derivatives:
Derivative liability	4,679	4,258
Indexed annuities/IUL embedded derivatives, included in contractholder funds \| Fair Value
Derivatives:
Derivative liability	4,679	4,258
Interest Rate Swaps \| Level 1
Derivatives:
Derivative liability	0
Interest Rate Swaps \| Level 2
Derivatives:
Derivative liability	0
Interest Rate Swaps \| Level 3
Derivatives:
Derivative liability	19
Interest Rate Swaps \| Fair Value
Derivatives:
Derivative liability	19
Call options \| Level 1
Derivatives:
Derivative liability	3
Call options \| Level 2
Derivatives:
Derivative liability	0
Call options \| Level 3
Derivatives:
Derivative liability	0
Call options \| Fair Value
Derivatives:
Derivative liability	3
Futures contracts \| Level 1
Derivatives:
Derivative liability		1
Futures contracts \| Level 2
Derivatives:
Derivative liability		0
Futures contracts \| Level 3
Derivatives:
Derivative liability		0
Futures contracts \| Fair Value
Derivatives:
Derivative liability		1
Asset-backed securities
Assets
Fixed maturity securities available for sale	15,115	14,342
Asset-backed securities \| Level 1
Assets
Fixed maturity securities available for sale	0	0
Asset-backed securities \| Level 2
Assets
Fixed maturity securities available for sale	7,379	7,220
Asset-backed securities \| Level 3
Assets
Fixed maturity securities available for sale	7,736	7,122
Asset-backed securities \| Fair Value
Assets
Fixed maturity securities available for sale	15,115	14,342
Commercial mortgage-backed securities
Assets
Fixed maturity securities available for sale	4,818	4,475
Commercial mortgage-backed securities \| Level 1
Assets
Fixed maturity securities available for sale	0	0
Commercial mortgage-backed securities \| Level 2
Assets
Fixed maturity securities available for sale	4,806	4,457
Commercial mortgage-backed securities \| Level 3
Assets
Fixed maturity securities available for sale	12	18
Commercial mortgage-backed securities \| Fair Value
Assets
Fixed maturity securities available for sale	4,818	4,475
Corporates
Assets
Fixed maturity securities available for sale	18,971	17,896
Corporates \| Level 1
Assets
Fixed maturity securities available for sale	25	25
Corporates \| Level 2
Assets
Fixed maturity securities available for sale	16,762	15,892
Corporates \| Level 3
Assets
Fixed maturity securities available for sale	2,184	1,979
Corporates \| Fair Value
Assets
Fixed maturity securities available for sale	18,971	17,896
Hybrids
Assets
Fixed maturity securities available for sale	633	618
Hybrids \| Level 1
Assets
Fixed maturity securities available for sale	99	95
Hybrids \| Level 2
Assets
Fixed maturity securities available for sale	534	523
Hybrids \| Level 3
Assets
Fixed maturity securities available for sale	0	0
Hybrids \| Fair Value
Assets
Fixed maturity securities available for sale	633	618
Municipals \| Level 1
Assets
Fixed maturity securities available for sale	0	0
Municipals \| Level 2
Assets
Fixed maturity securities available for sale	1,529	1,562
Municipals \| Level 3
Assets
Fixed maturity securities available for sale	18	49
Municipals \| Fair Value
Assets
Fixed maturity securities available for sale	1,547	1,611
Residential mortgage-backed securities
Assets
Fixed maturity securities available for sale	2,464	2,429
Residential mortgage-backed securities \| Level 1
Assets
Fixed maturity securities available for sale	0	0
Residential mortgage-backed securities \| Level 2
Assets
Fixed maturity securities available for sale	2,460	2,426
Residential mortgage-backed securities \| Level 3
Assets
Fixed maturity securities available for sale	4	3
Residential mortgage-backed securities \| Fair Value
Assets
Fixed maturity securities available for sale	2,464	2,429
U.S. Government
Assets
Fixed maturity securities available for sale	698	678
U.S. Government \| Level 1
Assets
Fixed maturity securities available for sale	682	662
U.S. Government \| Level 2
Assets
Fixed maturity securities available for sale	16	16
U.S. Government \| Level 3
Assets
Fixed maturity securities available for sale	0	0
U.S. Government \| Fair Value
Assets
Fixed maturity securities available for sale	698	678
Foreign Governments
Assets
Fixed maturity securities available for sale	320	324
Foreign Governments \| Level 1
Assets
Fixed maturity securities available for sale	0	0
Foreign Governments \| Level 2
Assets
Fixed maturity securities available for sale	315	308
Foreign Governments \| Level 3
Assets
Fixed maturity securities available for sale	5	16
Foreign Governments \| Fair Value
Assets
Fixed maturity securities available for sale	320	324
Preferred securities
Assets
Equity and preferred securities	542	621
Preferred securities \| Level 1
Assets
Equity and preferred securities	192	214
Preferred securities \| Level 2
Assets
Equity and preferred securities	342	399
Preferred securities \| Level 3
Assets
Equity and preferred securities	8	8
Preferred securities \| Fair Value
Assets
Equity and preferred securities	542	621
Equity securities \| Level 1
Assets
Equity and preferred securities	720	692
Equity securities \| Level 2
Assets
Equity and preferred securities	0	0
Equity securities \| Level 3
Assets
Equity and preferred securities	14	15
Equity securities \| NAV
Assets
Equity and preferred securities	59	59
Equity securities \| Fair Value
Assets
Equity and preferred securities	793	766
Other long-term investments \| Level 1
Assets
Other long-term investments	0	0
Other long-term investments \| Level 2
Assets
Other long-term investments	0	0
Other long-term investments \| Level 3
Assets
Other long-term investments	39	37
Other long-term investments \| Fair Value
Assets
Other long-term investments	$ 39	$ 37

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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