Earnings per Common Share (Details) (USD $)
In Millions, except Per Share data, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Numerator:    
Net income attributable to World Fuel $ 55.6 $ 50.7
Denominator:    
Weighted average common shares for basic earnings per common share 70.7 70.7
Effect of dilutive securities (in shares) 0.7 0.7
Weighted average common shares for diluted earnings per common share 71.4 71.4
Weighted average securities which are not included in the calculation of diluted earnings per common share (in shares) 0.9 0.5
Basic earnings per common share (in dollars per share) $ 0.79 $ 0.72
Diluted earnings per common share (in dollars per share) $ 0.78 $ 0.71