Goodwill (Details) (USD $)
In Millions, unless otherwise specified
1 Months Ended 12 Months Ended
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2010
Goodwill and Intangible Assets Disclosure [Abstract]        
Weight of income approach used in measurement of goodwill impairment 75.00%   75.00%  
Weight of market approach used in measurement of goodwill impairment 25.00%   25.00%  
Goodwill [Roll Forward]        
Goodwill   $ 1,366.2 $ 1,794.1  
Goodwill, Impairment Loss (427.8)   (427.8)  
Currency translation adjustment   (0.4)   (0.1)
Goodwill $ 1,366.2 $ 1,366.6 $ 1,366.2 $ 1,794.1