Earnings per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
Numerator:
Net income attributable to World Fuel	[1]	$ 52.4	$ 55.6
Denominator:
Weighted average common shares for basic earnings per common share	[1]	69.5	70.7
Effect of dilutive securities (in shares)	[1]	0.5	0.7
Weighted average common shares for diluted earnings per common share	[1]	70.0	71.4
Weighted average securities which are not included in the calculation of diluted earnings per common share (in shares)	[1]	0.9	0.9
Basic earnings per common share (in dollars per share)	[1]	$ 0.75	$ 0.79
Diluted earnings per common share (in dollars per share)	[1]	$ 0.75	$ 0.78

[1] Amounts may not add due to rounding