Restructuring Charges (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended	12 Months Ended	18 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014
Restructuring And Related Cost [Line Items]
Restructuring charges		$ 20
Payments to settle restructuring reserves	10		14
Severance Costs [Member]
Restructuring And Related Cost [Line Items]
Restructuring charges		14
Payments to settle restructuring reserves			10
Contract Termination And Other Associated Costs [Member]
Restructuring And Related Cost [Line Items]
Restructuring charges		6
Payments to settle restructuring reserves			$ 4