Business Segments (Details 2) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Accounts receivable, net:    
Accounts receivable, net $ 2,202.3 $ 2,307.9
Total assets:    
Total assets 4,788.0 4,880.0
Aviation Segment    
Accounts receivable, net:    
Accounts receivable, net 653.2 686.5
Allowance for bad debt 7.2 7.9
Marine segment    
Accounts receivable, net:    
Accounts receivable, net 870.6 974.0
Allowance for bad debt 8.4 8.4
Land Segment    
Accounts receivable, net:    
Accounts receivable, net 678.5 647.4
Allowance for bad debt 9.7 9.4
Operating Segments | Aviation Segment    
Total assets:    
Total assets 1,656.3 1,635.4
Operating Segments | Marine segment    
Total assets:    
Total assets 1,349.1 1,483.1
Operating Segments | Land Segment    
Total assets:    
Total assets 1,570.7 1,570.6
Corporate    
Total assets:    
Total assets $ 211.9 $ 190.9