Derivative Financial Instruments (Details 2) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Asset derivatives
Gross amount	$ 30	$ 92
Counter- party netting	0	0
Total	30	92
Liability derivatives
Gross amount	(307)	(356)
Counter- party netting	7	2
Total	(300)	(354)
OTC derivatives
Asset derivatives
Gross amount	15	7
Counter- party netting	(7)	(2)
Cash collateral (received) pledged	(4)	0
Total	4	5
Securities collateral (received) pledged	(1)	(4)
Net amount	3	1
Liability derivatives
Gross amount	(9)	(11)
Counter- party netting	7	2
Cash collateral (received) pledged	(8)	0
Total	(10)	(9)
Securities collateral (received) pledged	7	7
Net amount	$ (3)	$ (2)