Shares And Stockholders' Equity (Schedule of Reclassifications Out Of AOCI) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total realized gain (loss)	$ (117)	$ (7)	$ (480)	$ 5
Net investment income	1,355	1,232	2,606	2,465
Interest and debt expense	(70)	(68)	(141)	(159)
Commissions and other expenses	$ (1,272)	$ (1,177)	(2,446)	(2,234)
Unrealized Gain (Loss) on AFS Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total realized gain (loss)			(12)	(29)
Reclassifications before income tax benefit (expense)			(17)	(39)
Income tax benefit (expense)			4	8
Reclassifications, net of income tax			(13)	(31)
Unrealized Gain (Loss) on AFS Securities [Member] | Associated amortization of DAC, VOBA, DSI and DFEL [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total realized gain (loss)			(5)	(10)
Unrealized OTTI on AFS Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total realized gain (loss)			5
Reclassifications before income tax benefit (expense)			5
Income tax benefit (expense)			(1)
Reclassifications, net of income tax			4
Unrealized Gain (Loss) on Derivative Instruments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Nonoperating income expense			20	11
Reclassifications before income tax benefit (expense)			18	10
Income tax benefit (expense)			(4)	(2)
Reclassifications, net of income tax			14	8
Unrealized Gain (Loss) on Derivative Instruments [Member] | Interest Rate Contracts [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income			2	2
Interest and debt expense			(1)	(2)
Unrealized Gain (Loss) on Derivative Instruments [Member] | Foreign currency contracts [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total realized gain (loss)			4
Net investment income			15	11
Unrealized Gain (Loss) on Derivative Instruments [Member] | Associated amortization of DAC, VOBA, DSI and DFEL [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Commissions and other expenses			$ (2)	$ (1)