Fair Value Measurements (Details 3-Reported) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Fair Value [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Other noncurrent financial assets	$ 165	$ 189
Total financial assets	165	189
Financial liabilities
Other current financial liabilities	13	13
Long-term debt, including current portion	6,991	7,610
Deferred credits and other financial liabilities	141	94
Financial Liabilities Fair Value Disclosure	7,145	7,717
Carrying Amount [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Other noncurrent financial assets	164	186
Total financial assets	164	186
Financial liabilities
Other current financial liabilities	13	13
Long-term debt, including current portion	6,460	6,642
Deferred credits and other financial liabilities	140	94
Financial Liabilities Fair Value Disclosure	$ 6,613	$ 6,749