Segment Information (Reconciliation Of Income (Loss) From Operations By Segment To Consolidated Net Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Net income (loss)	$ 344	$ 398	$ 644	$ 727
Annuities Segment [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	255	227	494	443
Retirement Plan Services Segment [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	30	39	65	78
Life Insurance Segment [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	105	148	215	268
Group Protection Segment [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	19	2	13	21
Other Operations [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	(38)	(22)	(63)	(51)
Excluded realized gain (loss), tax, reconciling item [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	(23)	(3)	(83)	(42)
Income (loss) from reserve changes (net of related amortization) on business sold through reinsurance, after-tax [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations			1	1
Benefit ratio unlocking, tax, reconciling item [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Income (loss) from continuing operations	$ (4)	$ 7	$ 2	$ 9