Derivative Notional Amounts (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Foreign Exchange Contract [Member]    
Notional Disclosures [Abstract]    
Derivative, notional amount $ 1,020.2 $ 1,132.3
Commodity Contract (MMbtu) [Member]    
Notional Disclosures [Abstract]    
Nonmonetary derivative notional amount 36,300,000 24,400,000