Segment Information (Narrative) (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) division segment	Jun. 30, 2016 USD ($)
Segment Reporting Information [Line Items]
Income (loss) before income taxes and equity in earnings of operating joint ventures	$ 608	$ 1,341	$ 2,350	$ 3,073
Number of operating divisions | division			4
Number of reportable segments | segment			7
Out of period adjustment
Segment Reporting Information [Line Items]
Income (loss) before income taxes and equity in earnings of operating joint ventures		(148)
Individual Life | Out of period adjustment
Segment Reporting Information [Line Items]
Income (loss) before income taxes and equity in earnings of operating joint ventures		$ (148)