Derivatives (Net Derivative Gains Losses) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Components of Net Derivatives Gains (Losses)
Derivatives and hedging gains (losses)	$ (1,852)	$ 2,318	$ 3,177	$ 1,433
Embedded derivatives gains (losses)	801	(1,833)	(4,992)	(1,039)
Total net derivative gains (losses)	$ (1,051)	$ 485	$ (1,815)	$ 394