Derivative Instruments (Cumulative Basis Adjustments For Fair Value Hedges) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Fixed Maturity AFS Securities [Member]
Derivatives, Fair Value [Line Items]
Amortized cost of the hedged assets	$ 824	$ 776
Cumulative fair value hedging adjustment included in the amortized cost of the hedged assets	271	202
Long-term Debt [Member]
Derivatives, Fair Value [Line Items]
Amortized cost of the hedged liabilities	(900)	(1,035)
Cumulative fair value hedging adjustment included in the amortized cost of the hedged liabilities	(25)	(160)
Discontinued Hedges [Member] \| Long-term Debt [Member]
Derivatives, Fair Value [Line Items]
Cumulative fair value hedging adjustment included in the amortized cost of the hedged liabilities	$ (370)	$ (118)

Amortized cost of hedged asset

No definition available.

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- Definition

Amortized cost of hedged liabilities

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109999712-113959

+ Details

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

+ References

+ Details

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