Investments (Reconciliation Of Available-For-Sale Securities From Cost Basis To Fair Value) (Details) - Fixed Maturity AFS Securities [Member] - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	$ 97,789	$ 93,307
Gross Unrealized Gains	14,665	10,633
Gross Unrealized Losses	575	226
OTTI	21	(59)
Fair Value	111,858	103,773
Corporate Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	82,214	78,875
Gross Unrealized Gains	12,519	9,071
Gross Unrealized Losses	456	172
OTTI	19	(5)
Fair Value	94,258	87,779
ABS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	5,660	4,803
Gross Unrealized Gains	111	62
Gross Unrealized Losses	60	17
OTTI	1	(35)
Fair Value	5,710	4,883
U.S. Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	376	355
Gross Unrealized Gains	92	48
Fair Value	468	403
Foreign Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	355	326
Gross Unrealized Gains	80	62
Gross Unrealized Losses	3
Fair Value	432	388
RMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	2,732	2,820
Gross Unrealized Gains	301	179
Gross Unrealized Losses	2	9
OTTI	1	(18)
Fair Value	3,030	3,008
CMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	1,133	1,038
Gross Unrealized Gains	94	45
Gross Unrealized Losses	1	1
OTTI		(1)
Fair Value	1,226	1,083
State And Municipal Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	4,772	4,605
Gross Unrealized Gains	1,396	1,087
Gross Unrealized Losses	2	7
Fair Value	6,166	5,685
Hybrid And Redeemable Preferred Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	547	485
Gross Unrealized Gains	72	79
Gross Unrealized Losses	51	20
Fair Value	$ 568	$ 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.

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