Reinsurance - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Ceded Credit Risk [Line Items]
Maximum retention per single insured life on fixed and VUL insurance contracts	$ 20.0
Percent of mortality risk reinsured on newly issued non-term life insurance contracts	27.00%
Other investments	$ 4,757.0	$ 3,577.0
Deposit assets, net of allowance for credit losses	21,056.0	11,628.0
Realized gain (loss)	(4,934.0)	418.0	$ 859.0
Reinsurance ACL and deposit assets	76.0	315.0
LNBAR
Ceded Credit Risk [Line Items]
Reinsurance recoverables, case basis	15,600.0	2,200.0
Reinsurance recoverables	13,200.0
Reinsurance recoverables on unpaid losses	4,200.0
Reinsurance recoverable for unpaid claims and claims adjustments	14.0
Other investments	759.0
Investments and cash	112.0
Trust funded to support reinsurance receivable	13,000.0	2,200.0
Fortitude Re \| Fixed Annuities
Ceded Credit Risk [Line Items]
Reinsurance recoverables	10,500.0
Reinsurance recoverables on unpaid losses	2,700.0
Reinsurance recoverable for unpaid claims and claims adjustments	11.0
Deposit assets, net of allowance for credit losses	4,200.0
Resolution Life
Ceded Credit Risk [Line Items]
Reinsurance recoverables, case basis	5,000.0	5,000.0
Resolution Life \| Over-Collateralization
Ceded Credit Risk [Line Items]
Reinsurance recoverables	3,800.0	4,100.0
Realized gain (loss)			635.0
Protective
Ceded Credit Risk [Line Items]
Reinsurance recoverables	9,100.0	9,600.0
Protective \| Over-Collateralization
Ceded Credit Risk [Line Items]
Reinsurance recoverables	10,500.0	11,500.0
Athene Holding Ltd.
Ceded Credit Risk [Line Items]
Other investments	41.0	42.0
Deposit assets, net of allowance for credit losses	2,700.0	3,800.0
Reserves associated with modified coinsurance reinsurance arrangements	2,774.0	3,809.0
Letter of credit	83.0
Amount of amortization, after-tax, of deferred gain on business sold	33.0	25.0	$ 26.0
Athene Holding Ltd. \| Over-Collateralization
Ceded Credit Risk [Line Items]
Reserves associated with modified coinsurance reinsurance arrangements	77.0
Swiss Re
Ceded Credit Risk [Line Items]
Reinsurance recoverables, case basis	1,600.0	1,600.0
Trust funded to support reinsurance receivable	$ 656.0	$ 710.0

Amount, after-tax, of deferred gain on business sold through reinsurance amortized into income during the period.

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Maximum amount retained per single insured life issued on fixed and VUL insurance contracts.

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Disclosure of the percentage of mortality risk that is reinsured on newly issued non-term life insurance contracts.

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Amount of allowance for credit loss on reinsurance recoverable and deposit assets.

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The amount of reserves associated with modified coinsurance reinsurance arrangements for portions of the Company's deferred annuity business.

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Funds held in trust by the reinsurer to support the sale of the Entity's reinsurance business through an indemnity reinsurance agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of realized gain (loss) on investment in debt and equity securities.

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The carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement.

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Sum of investments and unrestricted cash as of the balance sheet date.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount of investments classified as other.

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The sum for all reinsurance arrangements of the known and estimated amount recoverable as of the balance sheet date from a given reinsurer for claims paid or incurred by the ceding insurer and associated claims settlement expenses for each reinsurance arrangement (or, the sum of all cases determined individually, probably applying different assumptions to each arrangement).

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Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to the ceding insurer but not yet paid and amounts expected for incurred losses and settlement expenses, which have not yet been reported to the ceding insurer.

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Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

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Amount before valuation allowance of reinsurance recoverables for losses reported to the ceding insurer but not yet paid, and for amounts expected based upon statistical projections and other measures of incurred losses and loss settlement expenses which have not yet been reported to the ceding insurer.

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