Investments (Reconciliation Of Available-For-Sale Securities From Cost Basis To Fair Value) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	$ 98,817		$ 94,295
ACL	(22)	$ (20)	0
Fair Value	113,519		105,200
Corporate Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
ACL	(20)	$ (20)
RMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
ACL	(1)
ABS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
ACL	(1)
Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	98,817		94,295
Gross unrealized gains	15,323		11,086
Gross unrealized losses	599		240
ACL	22
OTTI			(59)
Fair Value	113,519		105,200
Fixed Maturity AFS Securities [Member] \| Corporate Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	82,788		79,417
Gross unrealized gains	13,102		9,479
Gross unrealized losses	480		184
ACL	20
OTTI			(4)
Fair Value	95,390		88,716
Fixed Maturity AFS Securities [Member] \| U.S. Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	404		384
Gross unrealized gains	100		51
Fair Value	504		435
Fixed Maturity AFS Securities [Member] \| State And Municipal Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	4,958		4,778
Gross unrealized gains	1,437		1,113
Gross unrealized losses	2		7
Fair Value	6,393		5,884
Fixed Maturity AFS Securities [Member] \| Foreign Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	358		329
Gross unrealized gains	81		64
Gross unrealized losses	3
Fair Value	436		393
Fixed Maturity AFS Securities [Member] \| RMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	2,951		3,042
Gross unrealized gains	324		190
Gross unrealized losses	2		10
ACL	1
OTTI			(19)
Fair Value	3,272		3,241
Fixed Maturity AFS Securities [Member] \| 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
Fixed Maturity AFS Securities [Member] \| ABS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	5,666		4,810
Gross unrealized gains	111		62
Gross unrealized losses	60		18
ACL	1
OTTI			(35)
Fair Value	5,716		4,889
Fixed Maturity AFS Securities [Member] \| Hybrid And Redeemable Preferred Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	559		497
Gross unrealized gains	74		82
Gross unrealized losses	51		20
Fair Value	$ 582		$ 559

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

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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