Segment Information (Reconciliation Of Revenue From Segments To Consolidated) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Total revenues	$ 3,965	$ 3,609
Annuities Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,174	1,073
Retirement Plan Services Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	293	292
Life Insurance Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,700	1,660
Group Protection Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,138	553
Other Operations [Member]
Segment Reporting Information [Line Items]
Total revenues	57	67
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Excluded realized gain (loss), pre-tax	(400)	(35)
Amortization of DFEL associated with benefit ratio unlocking, pre-tax	$ 3	$ (1)