Segment Information Segment Information (Reconciliation of Operating Revenues to Total Revenues) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Revenues	$ 5,798	$ 2,260	$ 7,872
Annuities
Segment Reporting Information [Line Items]
Revenues	3,721	4,423	4,665
Life
Segment Reporting Information [Line Items]
Revenues	1,036	1,036	881
Run-off
Segment Reporting Information [Line Items]
Revenues	2,148	2,313	2,366
Corporate & Other
Segment Reporting Information [Line Items]
Revenues	250	338	398
Segment Reconciling Items
Segment Reporting Information [Line Items]
Revenues	$ (1,357)	$ (5,850)	$ (438)