Shares And Stockholders' Equity (Schedule of Reclassifications Out Of AOCI) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total realized gain (loss)	$ (362)	$ 12
Net investment income	1,251	1,233
Interest and debt expense	(71)	(91)
Commissions and other expenses	(1,176)	(1,057)
Unrealized Gain (Loss) on AFS Securities [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total realized gain (loss)	(15)	(18)
Reclassifications before income tax benefit (expense)	(16)	(22)
Income tax benefit (expense)	3	5
Reclassifications, net of income tax	(13)	(17)
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)	(1)	(4)
Unrealized Gain (Loss) on Derivative Instruments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Nonoperating income expense	8	3
Reclassifications before income tax benefit (expense)	7	2
Income tax benefit (expense)	(1)
Reclassifications, net of income tax	6	2
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	1
Interest and debt expense	(1)	(3)
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
Net investment income	7	5
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	$ (1)	$ (1)