Shares And Stockholders' Equity (Schedule of Reclassifications Out Of AOCI) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total realized gain (loss)	$ (24)	$ (362)
Net investment income	1,375	1,251
Interest and debt expense	(68)	(71)
Commissions and other expenses	(1,085)	(1,176)
Unrealized Gain (Loss) on AFS Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total realized gain (loss)	(2)	(15)
Reclassifications before income tax benefit (expense)	30	(16)
Income tax benefit (expense)	(6)	3
Reclassifications, net of income tax	24	(13)
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)	32	(1)
Unrealized Gain (Loss) on Derivative Instruments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Nonoperating income expense	9	8
Reclassifications before income tax benefit (expense)	3	7
Income tax benefit (expense)	(1)	(1)
Reclassifications, net of income tax	2	6
Unrealized Gain (Loss) on Derivative Instruments [Member] | Interest Rate Contracts [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income		1
Interest and debt expense	(3)	(1)
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)	1	1
Net investment income	11	7
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	$ (6)	$ (1)