Segment Information (Reconciliation Of Revenue From Segments To Consolidated) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	$ 3,243	$ 3,304
Annuities Segment [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	1,039	989
Retirement Plan Services Segment [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	267	273
Life Segment [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	1,478	1,432
Group Protection Segment [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	534	605
Other Operations [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	82	95
Excluded realized gain (loss) pre-tax [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	(158)	(91)
Amortization of deferred gain (loss) on reinsurance related to reserve changes, tax, reconciling item [Member]
Schedule Of Segment Reporting And Reconcilliation [Line Items]
Total revenues	$ 1	$ 1