Employee Benefit Plans (Details) (Other Postretirement Benefit Plans, Defined Benefit [Member], USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 3	$ 4	$ 7	$ 7
Expected return on plan assets	(2)	(2)	(3)	(3)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(1)	0	(1)	0
Amortization of loss	1	1	1	2
Amortization of transition obligation	1	1	2	2
Net periodic cost	2	4	6	8
Expected contribution to postretirement benefit plan in current year			7
Total contribution to the plan during the period	$ 2		$ 4