Derivative Financial Instruments (Details 2) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Asset derivatives
Gross amount	$ 56	$ 57
Counter- party netting	0	(1)
Total asset derivatives	56	56
Liability derivatives
Gross amount	(338)	(313)
Counter- party netting	6	5
Total liability derivatives	(332)	(308)
OTC derivatives
Asset derivatives
Gross amount	9	15
Counter- party netting	(6)	(6)
Cash collateral (received) pledged	(3)	(5)
Total asset derivatives	0	4
Securities collateral (received) pledged	0	(1)
Net amount	0	3
Liability derivatives
Gross amount	(14)	(9)
Counter- party netting	6	6
Cash collateral (received) pledged	(5)	(5)
Total liability derivatives	(13)	(8)
Securities collateral (received) pledged	7	7
Net amount	$ (6)	$ (1)