Segment Information (Total Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total assets	$ 205,026	$ 195,830
Annuities
Segment Reporting Information [Line Items]
Total assets	145,246	137,079
Life
Segment Reporting Information [Line Items]
Total assets	15,168	14,928
Run-off
Segment Reporting Information [Line Items]
Total assets	33,182	32,390
Corporate & Other
Segment Reporting Information [Line Items]
Total assets	$ 11,430	$ 11,433