Divestitures and Business Combinations (Details 3) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Dec. 31, 2014
Acquisitions [Line Items]    
Goodwill $ 823.5 $ 859.5
Goodwill increase $ (9.7)  
Minimum | Customer contracts and relationships    
Acquisitions [Line Items]    
Useful life (years) 8 years  
Minimum | Covenants not to compete    
Acquisitions [Line Items]    
Useful life (years) 4 years  
Maximum | Customer contracts and relationships    
Acquisitions [Line Items]    
Useful life (years) 30 years  
Maximum | Covenants not to compete    
Acquisitions [Line Items]    
Useful life (years) 5 years