Derivatives (Credit Risk on Freestanding Derivatives) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Credit Derivatives [Line Items]
Estimated Fair Value of Derivatives in a Net Liability Position (1)	$ 918	$ 959
Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated Fair Value of Collateral Provided:	1,096	1,063
Derivatives Subject to Credit- Contingent Provisions
Credit Derivatives [Line Items]
Estimated Fair Value of Derivatives in a Net Liability Position (1)	694	874
Derivatives Subject to Credit- Contingent Provisions \| Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated Fair Value of Collateral Provided:	874	983
Derivatives Not Subject to Credit- Contingent Provisions
Credit Derivatives [Line Items]
Estimated Fair Value of Derivatives in a Net Liability Position (1)	224	85
Derivatives Not Subject to Credit- Contingent Provisions \| Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated Fair Value of Collateral Provided:	$ 222	$ 80

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959

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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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- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959

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