Derivatives (Credit Risk on Freestanding Derivatives) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Credit Derivatives [Line Items]
Collateral Amount Not Provided Due to Downgrade Threshold	$ 15
Estimated fair value of derivatives in a net liability position (1)	2,447	$ 2,049
Derivative assets	8,737	11,411
Derivative liabilities	6,298	6,975
Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	3,017	2,267
Accrued Liabilities [Member]
Credit Derivatives [Line Items]
Derivative assets	181	166
Derivative liabilities	9	0
Derivatives Subject to Credit-Contingent Provisions
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	2,443	2,049
Derivatives Subject to Credit-Contingent Provisions \| Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	3,011	2,267
Derivatives Not Subject to Credit-Contingent Provisions
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	4	0
Derivatives Not Subject to Credit-Contingent Provisions \| Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	$ 6	$ 0

Collateral Amount Not Provided Due to Downgrade Threshold

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4H

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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

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483444/210-20-55-22

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- Definition

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.

+ References

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
-Section 50
-Paragraph 4H
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