Segment Information (Reconciliation Of Revenue From Segments To Consolidated) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Total revenues	$ 4,310	$ 4,020	$ 8,275	$ 7,629
Annuities Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,156	1,106	2,330	2,180
Retirement Plan Services Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	299	292	592	584
Life Insurance Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,802	1,680	3,502	3,340
Group Protection Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,155	937	2,293	1,490
Other Operations [Member]
Segment Reporting Information [Line Items]
Total revenues	58	58	116	125
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Excluded realized gain (loss), pre-tax	(161)	$ (53)	(562)	(89)
Amortization of DFEL associated with benefit ratio unlocking, pre-tax	$ 1		$ 4	$ (1)