Fair Value of Financial Instruments (Components Of The Transfers In And Out Of Level 3) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	$ 1,212	$ 192	$ 105
Transfers Out of Level 3	(729)	(1,014)	(567)
Transfers Into or Out of Level 3, Net	483	(822)	(462)
Corporate Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	343	173	78
Transfers Out of Level 3	(243)	(222)	(140)
Transfers Into or Out of Level 3, Net	100	(49)	(62)
RMBS [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	1
Transfers Out of Level 3	(10)	(17)	(12)
Transfers Into or Out of Level 3, Net	(9)	(17)	(12)
ABS [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	20	9
Transfers Out of Level 3	(221)	(495)	(206)
Transfers Into or Out of Level 3, Net	(201)	(486)	(206)
U.S. Government Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	5	5
Transfers Out of Level 3	(5)
Transfers Into or Out of Level 3, Net		5
CMBS [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3			1
Transfers Out of Level 3		(7)	(40)
Transfers Into or Out of Level 3, Net		(7)	(39)
Hybrid And Redeemable Preferred Securities [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	18
Transfers Into or Out of Level 3, Net	18
Equity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Out of Level 3			(162)
Transfers Into or Out of Level 3, Net			(162)
Mortgage Loans On Real Estate [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	787
Transfers Into or Out of Level 3, Net	787
Trading Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	33	5
Transfers Out of Level 3	(34)	(273)	(7)
Transfers Into or Out of Level 3, Net	(1)	$ (268)	(7)
Equity Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3	5		26
Transfers Into or Out of Level 3, Net	5		$ 26
Derivative Investments [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Out of Level 3	(216)
Transfers Into or Out of Level 3, Net	$ (216)

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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