Fair Value Measurements (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Assets:
Investments	$ 54	$ 56
Foreign Exchange Contracts	21	30
Total Assets at Fair Value	75	86
Liabilities:
Foreign Exchange Contracts	14	4
Total Liabilities at Fair Value	14	4
Fair value of Long term fixed rate and Variable rate debt, excluding capital leases (Abstract) [Abstract]
Carrying amount - liability	5,908	6,305
Prior Period Reclassification Adjustment	452
Fixed Rate Debt, Excluding Capital Leases
Fair value of Long term fixed rate and Variable rate debt, excluding capital leases (Abstract) [Abstract]
Carrying amount - liability	3,623	3,680
Fair Value - liability	3,838	3,773
Variable Rate Debt, Excluding Capital Leases
Fair value of Long term fixed rate and Variable rate debt, excluding capital leases (Abstract) [Abstract]
Carrying amount - liability	2,285	2,625
Fair Value - liability	2,285	2,622
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)
Assets:
Investments	54	56
Foreign Exchange Contracts	0	0
Total Assets at Fair Value	54	56
Liabilities:
Foreign Exchange Contracts	0	0
Total Liabilities at Fair Value	0	0
Fair value of Long term fixed rate and Variable rate debt, excluding capital leases (Abstract) [Abstract]
Fair Value - liability	4,508	4,603
Significant Other Observable Inputs (Level 2)
Assets:
Investments	0	0
Foreign Exchange Contracts	21	30
Total Assets at Fair Value	21	30
Liabilities:
Foreign Exchange Contracts	14	4
Total Liabilities at Fair Value	14	4
Significant Unobservable Inputs (Level 3)
Assets:
Investments	0	0
Foreign Exchange Contracts	0	0
Total Assets at Fair Value	0	0
Liabilities:
Foreign Exchange Contracts	0	0
Total Liabilities at Fair Value	$ 0	$ 0