Derivative Financial Instruments - Carrying Amounts of Derivative Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	$ 38,139	$ 34,896
Assets	737	827
Liabilities	5,240	5,121
Derivatives designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	410	39
Assets	10	2
Liabilities	1	0
Derivatives designated as hedging instruments \| Interest rate swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	350	0
Assets	9	0
Liabilities	0	0
Derivatives designated as hedging instruments \| Foreign currency swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	60	39
Assets	1	2
Liabilities	1	0
Derivatives not designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	37,729	34,857
Assets	727	825
Liabilities	5,239	5,121
Derivatives not designated as hedging instruments \| Interest rate swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	5,655	5,145
Assets	62	19
Liabilities	0	10
Derivatives not designated as hedging instruments \| Equity options
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	31,986	29,594
Assets	632	773
Liabilities	1	0
Derivatives not designated as hedging instruments \| Futures contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	0	0
Assets	1	0
Liabilities	0	0
Derivatives not designated as hedging instruments \| Other derivative investments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	88	118
Assets	0	1
Liabilities	0	0
Derivatives not designated as hedging instruments \| Other embedded derivatives
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	0	0
Assets	32	32
Liabilities	0	0
Derivatives not designated as hedging instruments \| Indexed annuities/indexed universal life insurance ("IUL") embedded derivatives, included in Contractholder funds
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	0	0
Assets	0	0
Liabilities	5,316	5,220
Derivatives not designated as hedging instruments \| Reinsurance related embedded derivatives
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	0	0
Assets	0	0
Liabilities	$ (78)	$ (109)

Fair value, before effects of master netting arrangements, of a financial asset or other 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 assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before 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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Nominal or face amount used to calculate payment on derivative.

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