Segment Information (Reconciliation Of Revenue From Segments To Consolidated) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Total revenues	$ 4,638	$ 4,264	$ 12,913	$ 11,893
Annuities Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,117	1,118	3,447	3,297
Retirement Plan Services Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	298	294	890	878
Life Insurance Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	2,098	1,766	5,600	5,106
Group Protection Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,137	1,128	3,430	2,618
Other Operations [Member]
Segment Reporting Information [Line Items]
Total revenues	50	56	166	182
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Excluded realized gain (loss), pre-tax	(61)	$ (98)	(623)	$ (188)
Amortization of DFEL associated with benefit ratio unlocking, pre-tax	$ (1)		$ 3