Employee Benefit Plans Postretirement (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Net benefit cost	$ 0	$ (1)
Other Postretirement Benefit Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Prior service cost (benefit)	(5)	(5)
Actuarial loss	1	1
Net benefit cost	(4)	(4)
Defined Benefit Plan, Contributions by Employer	1
Defined Benefit Plan Estimated Total Employer Contributions in Current Fiscal Year	4
Defined Benefit Plans, Estimated Future Employer Contributions in Current Fiscal Year	$ 3