Reinsurance - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
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	25.00%
Investments	$ 123,388.0	$ 117,325.0
Other investments	6,272.0	4,757.0
Deposit assets, net of allowance for credit losses	30,537.0	21,514.0
Reinsurance recoverables, net of allowance for credit losses	48,943.0	45,110.0
Reinsurance recoverable, allowance for credit loss	95.0	76.0
Lincoln Pinehurst Reinsurance Company (Bermuda)
Ceded Credit Risk [Line Items]
Deposits assets	7,900.0
Investments	11,500.0
Reserves associated with modified coinsurance reinsurance arrangements	11,515.0
LNBAR
Ceded Credit Risk [Line Items]
Reinsurance recoverables	14,200.0	13,200.0
Reinsurance recoverables on unpaid losses	4,100.0	4,200.0
Reinsurance recoverables on unpaid losses, amortization	159.0	14.0
Other investments	1,400.0	871.0
Trust funded to support reinsurance receivable	12,200.0	13,000.0
Resolution Life
Ceded Credit Risk [Line Items]
Reinsurance recoverables, net of allowance for credit losses	4,900.0	5,000.0
Reinsurance recoverable for paid and unpaid claims and claims adjustments	3,800.0	3,800.0
Commonwealth
Ceded Credit Risk [Line Items]
Deposits assets	9,500.0	6,200.0
Investments	9,000.0	5,900.0
Protective
Ceded Credit Risk [Line Items]
Reinsurance recoverables, net of allowance for credit losses	8,400.0	9,100.0
Reinsurance recoverable for paid and unpaid claims and claims adjustments	9,900.0	10,500.0
Athene Holding Ltd.
Ceded Credit Risk [Line Items]
Other investments	54.0	41.0
Reinsurance ACL and deposit assets	2,100.0	2,700.0
Reserves associated with modified coinsurance reinsurance arrangements	2,067.0	2,774.0
Letter of credit	63.0
Amount of amortization, after-tax, of deferred gain on business sold	26.0	33.0	$ 25.0
Athene Holding Ltd. \| Over-Collateralization
Ceded Credit Risk [Line Items]
Reserves associated with modified coinsurance reinsurance arrangements	61.0
Swiss Re
Ceded Credit Risk [Line Items]
Trust funded to support reinsurance receivable	617.0	656.0
Reinsurance recoverables, net of allowance for credit losses	1,300.0	1,600.0
Fixed Annuities \| Lincoln Pinehurst Reinsurance Company (Bermuda)
Ceded Credit Risk [Line Items]
Reinsurance recoverables	3,700.0
Reinsurance recoverables on unpaid losses	14.0
Fixed Annuities \| Fortitude Re
Ceded Credit Risk [Line Items]
Reinsurance recoverables	10,600.0	10,500.0
Reinsurance recoverables on unpaid losses	2,600.0	2,700.0
Reinsurance recoverables on unpaid losses, amortization	90.0	11.0
Deposit assets, net of allowance for credit losses	$ 3,000.0	$ 4,200.0

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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Reinsurance Recoverables On Unpaid Losses, Amortization

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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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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 the carrying amounts as of the balance sheet date of all investments.

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Amount, after valuation allowance, recoverable under reinsurance contracts including premium paid 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 of allowance for credit loss on reinsurance recoverable.

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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, after 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, policy benefits and policy reserves. Excludes premiums paid under reinsurance contracts.

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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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