Segment Information (Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total assets	$ 195,830	$ 212,045
Separate account assets	91,511	110,156
Separate account liabilities	91,511	110,156
Annuities
Segment Reporting Information [Line Items]
Total assets	137,079	149,920
Separate account assets	88,138	105,140
Separate account liabilities	88,138	105,140
Life
Segment Reporting Information [Line Items]
Total assets	14,928	13,044
Separate account assets	1,732	1,915
Separate account liabilities	1,732	1,915
Run-off
Segment Reporting Information [Line Items]
Total assets	32,390	36,719
Separate account assets	1,641	3,101
Separate account liabilities	1,641	3,101
Corporate & Other
Segment Reporting Information [Line Items]
Total assets	11,433	12,362
Separate account assets	0	0
Separate account liabilities	$ 0	$ 0