Investments (Reconciliation Of Available-For-Sale Securities From Cost Basis To Fair Value) (Details) - Fixed Maturity AFS Securities [Member] - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	$ 100,682	$ 93,307
Gross Unrealized Gains	16,114	10,633
Gross Unrealized Losses	412	226
OTTI	12	(59)
Fair Value	116,372	103,773
Corporate Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	83,945	78,875
Gross Unrealized Gains	13,813	9,071
Gross Unrealized Losses	341	172
OTTI	11	(5)
Fair Value	97,406	87,779
ABS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	6,465	4,803
Gross Unrealized Gains	140	62
Gross Unrealized Losses	22	17
OTTI		(35)
Fair Value	6,583	4,883
U.S. Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	369	355
Gross Unrealized Gains	91	48
Fair Value	460	403
Foreign Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	353	326
Gross Unrealized Gains	81	62
Gross Unrealized Losses	3
Fair Value	431	388
RMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	2,654	2,820
Gross Unrealized Gains	310	179
Gross Unrealized Losses		9
OTTI	1	(18)
Fair Value	2,963	3,008
CMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	1,308	1,038
Gross Unrealized Gains	114	45
Gross Unrealized Losses	1	1
OTTI		(1)
Fair Value	1,421	1,083
State And Municipal Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	5,043	4,605
Gross Unrealized Gains	1,477	1,087
Gross Unrealized Losses	3	7
Fair Value	6,517	5,685
Hybrid And Redeemable Preferred Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	545	485
Gross Unrealized Gains	88	79
Gross Unrealized Losses	42	20
Fair Value	$ 591	$ 544

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- Definition

Unrealized other than temporary impairment losses, investments, available-for-sale securities.

+ References

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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