Summary of Significant Accounting Policies - Other Intangible Assets (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended 1 Months Ended 3 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2010
Sep. 30, 2012
Trademarks/brands
Sep. 30, 2011
Trademarks/brands
Sep. 30, 2012
Customer relationships
Sep. 30, 2011
Customer relationships
Sep. 30, 2011
Trademarks/brands
Jun. 30, 2011
Trademarks/brands
Sep. 30, 2010
Trademarks/brands
Sep. 30, 2012
Trademarks/brands
Finite-Lived and Indefinite-Lived, Intangible Assets                      
Amortization of intangible assets $ 12.6 $ 12.6 $ 12.7                
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]                      
2012 12.6                    
2013 12.4                    
2014 12.4                    
2015 12.4                    
2016 12.4                    
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]                      
Carrying amount       543.6 543.6            
Finite-Lived Intangible Assets [Abstract]                      
Finite-Lived Intangible Assets, Gross 244.9 244.9       153.9 153.9 91.0     91.0
Finite-Lived Intangible Assets, Accumulated Amortization 52.5 39.9       32.1 24.4 15.5     20.4
Finite-Lived Intangible Assets, Net 192.4 205.0       121.8 129.5 75.5     70.6
Intangible Assets, Net (Excluding Goodwill) [Abstract]                      
Carrying amount, total 788.5 788.5                  
Other intangible assets, net 736.0 748.6                  
Indefinite-lived Intangible Assets, Impairment Losses               $ 106.6 $ 32.1 $ 19.4