Shares And Stockholders' Equity (Components And Changes In Accumulated OCI) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of beginning-of-year	$ 5,673
Less:
Balance as of end-of-period	7,323
Unrealized Gain (Loss) on AFS Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of beginning-of-year	5,983	$ 557
Unrealized holding gains (losses) arising during the period	3,775	6,933
Change in foreign currency exchange rate adjustment	(93)	3
Change in DAC, VOBA, DSI, future contract benefits and other contract holder funds	(1,351)	(1,903)
Income tax benefit (expense)	(495)	(1,070)
Less:
Reclassification adjustment for gains (losses) included in net income (loss)	(44)	(12)
Associated amortization of DAC, VOBA, DSI, and DFEL	62	(5)
Income tax benefit (expense)	(4)	4
Less:
Balance as of end-of-period	7,850	4,533
Unrealized Gain (Loss) on AFS Securities [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of beginning-of-year	45
Unrealized OTTI on AFS Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of beginning-of-year	45	33
(Increases) attributable to:
Gross OTTI recognized in OCI during the period		(16)
Change in DAC, VOBA, DSI and DFEL		1
Income tax benefit (expense)		3
Decreases attributable to
Changes in fair value, sales, maturities or other settlements of AFS securities		19
Change in DAC, VOBA, DSI, and DFEL		(3)
Income tax benefit (expense)		(3)
Less:
Balance as of end-of-period		34
Unrealized OTTI on AFS Securities [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of beginning-of-year	(45)
Unrealized Gain (Loss) on Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of beginning-of-year	(11)	139
Unrealized holding gains (losses) arising during the period	(192)	(32)
Change in foreign currency exchange rate adjustment	97	(5)
Decreases attributable to
Change in DAC, VOBA, DSI and DFEL	(116)	(5)
Income tax benefit (expense)	43	8
Less:
Reclassification adjustment for gains (losses) included in net income (loss)	23	20
Associated amortization of DAC, VOBA, DSI and DFEL	(19)	(2)
Income tax benefit (expense)	(1)	(4)
Balance as of end-of-period	(182)	91
Foreign Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of beginning-of-year	(17)	(23)
Change in foreign currency exchange rate adjustment	(11)
Less:
Balance as of end-of-period	(28)	(23)
Funded Status of Employee Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of beginning-of-year	(327)	(299)
Less:
Adjustment arising during the period	10
Balance as of end-of-period	$ (317)	$ (299)