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]
Excluded realized gain (loss), pre-tax	$ (391)	$ (27)
Total revenues	3,764	3,404
Annuities Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,088	984
Retirement Plan Services Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	289	288
Life Insurance Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,584	1,549
Group Protection Segment [Member]
Segment Reporting Information [Line Items]
Total revenues	1,138	552
Other Operations [Member]
Segment Reporting Information [Line Items]
Total revenues	$ 56	$ 58