Derivatives and Fair Value Measurements (Details 2) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Derivatives, Fair Value [Line Items]
Derivative Assets, Current	$ 319.5	$ 313.8
Derivative Assets, Noncurrent	230.2	240.7
Derivative Liabilities, Current	6.1	11.4
Derivative Liabilities, Noncurrent	6.9	19.5
Foreign Exchange Contract [Member] | Cash flow hedges [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets, Current	286.7	270.4
Derivative Assets, Noncurrent	225.0	229.0
Derivative Liabilities, Current	0	4.3
Derivative Liabilities, Noncurrent	0	4.5
Commodity contracts [Member] | Cash flow hedges [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets, Current	32.8	43.4
Derivative Assets, Noncurrent	5.2	11.7
Derivative Liabilities, Current	6.1	7.1
Derivative Liabilities, Noncurrent	$ 6.9	$ 15.0