Derivative Financial Instruments (Details 2) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Asset derivatives
Gross amount	$ 64	$ 92
Counter- party netting	(1)	0
Net amount on balance sheet	63	92
Liability derivatives
Gross amount	(329)	(356)
Counter- party netting	5	2
Net amount on balance sheet	(324)	(354)
OTC derivatives
Asset derivatives
Gross amount	11	7
Counter- party netting	(6)	(2)
Cash collateral (received) pledged	(3)	0
Net amount on balance sheet	2	5
Securities collateral (received) pledged	0	(4)
Net amount	2	1
Liability derivatives
Gross amount	(9)	(11)
Counter- party netting	6	2
Cash collateral (received) pledged	(5)	0
Net amount on balance sheet	(8)	(9)
Securities collateral (received) pledged	7	7
Net amount	$ (1)	$ (2)