Segment Information (Reconciliation Of Income (Loss) From Operations By Segment To Consolidated Net Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Gain (loss) on early extinguishment of debt, after-tax			$ (15)
Net income (loss)	$ 398	$ (161)	356	$ 454
Excluded Realized Gain (Loss), After-Tax [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Net income (loss)	452	(49)	(156)	(492)
Gain (Loss) On Early Extinguishment Of Debt, After-Tax [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Net income (loss)		(33)	(12)	(33)
Benefit Ratio Unlocking, After-Tax [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Net income (loss)	83	(2)	17	186
Acquisition And Integration Costs Related To Mergers And Acquisitions, After-Tax [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Net income (loss)	4	31	12	80
Annuities Segment [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Net income (loss)	196	169	694	686
Retirement Plan Services Segment [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Net income (loss)	50	44	119	125
Life Insurance Segment [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Net income (loss)	(311)	(245)	(177)	79
Group Protection Segment [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Net income (loss)	6	61	85	184
Other Operations [Member]
Reconciliation of Net Income (Loss) from Segments to Consolidated [Abstract]
Net income (loss)	$ (74)	$ (75)	$ (202)	$ (201)