Fair Value Measurements (Details 3) In Millions, unless otherwise specified	Sep. 30, 2013 Eurobond Due 2014 EUR (€)	Sep. 30, 2013 Carrying Amount USD ($)	Dec. 31, 2012 Carrying Amount USD ($)	Sep. 30, 2013 Carrying Amount Eurobond Due 2014 USD ($)	Dec. 31, 2012 Carrying Amount Eurobond Due 2014 USD ($)	Sep. 30, 2013 Fair Value USD ($)	Dec. 31, 2012 Fair Value USD ($)	Sep. 30, 2013 Fair Value Eurobond Due 2014 USD ($)	Dec. 31, 2012 Fair Value Eurobond Due 2014 USD ($)
Financial Instruments
Eurobond securities (long-term in 2012 and short-term at period end)				$ 1,404	$ 1,383			$ 1,435	$ 1,443
Long-term debt, excluding current portion and Eurobond securities due 2014		3,533	3,533			3,695	3,920
Principal amount	€ 1,025