Derivative Financial Instruments and Risk Management (Details 4) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Derivative
Balance at beginning of period, net of tax			$ (5)	$ (5)
Gains (losses) deferred during the period, net of tax	$ 0	$ (2)	1	(4)
(Gains) losses reclassified to earnings, net of tax	1	1	2	2
Balance at end of period, net of tax	(2)	(7)	(2)	(7)
Beginning balance, tax			3	3
Gains (losses) deferred during the period, tax	0	1	(1)	1
(Gains) losses reclassified to earnings, tax	(1)	0	(1)	0
Ending balance, tax	$ 1	$ 4	$ 1	$ 4