Derivatives - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Notional Amount	$ 12,379,000,000	$ 25,097,000,000
Invested assets supporting Modco	877,000,000	645,000,000
Loss reclassification from ACOI, estimated net amount to be transferred	0
Reclassifications from AOCI to earnings resulting from the discontinuance of cash-flow hedges	0	0
Reinsurance recoverables	(23,000,000)	874,000,000
Margin deposit assets	42,000,000	15,000,000
Derivative asset, collateral, obligation to return cash, offset	130,000,000	187,000,000
Securities received as collateral	89,000,000	262,000,000
Asset Pledged as Collateral \| Cash Deposits
Derivative [Line Items]
Reinsurance recoverables	265,000,000	5,000,000
Asset Pledged as Collateral \| Securities
Derivative [Line Items]
Reinsurance recoverables	58,000,000	106,000,000
Fair value securities
Derivative [Line Items]
Securities received as collateral	1,000,000	79,000,000
Not Designated as Hedging Instrument
Derivative [Line Items]
Notional Amount	12,129,000,000	24,847,000,000
Reinsurance recoverables	6,000,000	874,000,000
Interest rate swaps \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional Amount	$ 0	$ 276,000,000

Amount of invested assets supporting other policyholder fund liabilities under a modified coinsurance agreement.

No definition available.

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- Definition

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ References

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- Definition

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.

+ References

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
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- Definition

The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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- Definition

Amount, before tax, of reclassification from accumulated other comprehensive income (AOCI) for gain (loss) from discontinuance of cash flow hedge included in assessment of hedge effectiveness.

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The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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