Derivative Financial Instruments (Details 2) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Asset derivatives
Asset derivatives gross amount	$ 65	$ 63
Asset derivatives, Gross liability	(12)	(2)
Derivative assets net amount on balance sheet	53	61
Liability derivatives
Liability derivatives gross amount	(346)	(329)
Liability derivatives, Gross asset	9	6
Derivative liabilities net amount on balance sheet	(337)	(323)
OTC derivatives
Asset derivatives
Asset derivatives gross amount	21	21
Asset derivatives, Gross liability	(21)	(8)
Derivative, Collateral, Right to Reclaim Cash	6
Derivative asset offsets under cash collateral received		(5)
Derivative assets net amount on balance sheet	6	8
Derivative assets pledged under securities collateral	0	(4)
Derivative Asset, Fair Value, Amount Offset Against Collateral	6	4
Liability derivatives
Liability derivatives gross amount	(34)	(25)
Liability derivatives, Gross asset	21	8
Derivative liability offsets under cash collateral pledged	(5)	(1)
Derivative liabilities net amount on balance sheet	(18)	(18)
Derivative liabilities received under securities collateral	10	9
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ (8)	$ (9)