Derivatives (Credit Risk on Freestanding Derivatives) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	$ 1,697	$ 1,185
Derivative, Collateral, Right to Reclaim Cash	206	238
Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	1,680	1,224
Derivatives Subject to Credit- Contingent Provisions
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	1,687	1,182
Derivatives Subject to Credit- Contingent Provisions \| Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	1,673	1,222
Derivatives Not Subject to Credit- Contingent Provisions
Credit Derivatives [Line Items]
Estimated fair value of derivatives in a net liability position (1)	10	3
Derivatives Not Subject to Credit- Contingent Provisions \| Fixed maturity securities AFS
Credit Derivatives [Line Items]
Estimated fair value of collateral provided:	$ 7	$ 2

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=121590274&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

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=d3e41678-113959

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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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=121590274&loc=SL5624258-113959

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