Quarterly report pursuant to Section 13 or 15(d)

Investment Income, Net (Schedule of Investment Income, Net) (Details)

v3.7.0.1
Investment Income, Net (Schedule of Investment Income, Net) (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Feb. 28, 2017
Feb. 29, 2016
Feb. 28, 2017
Feb. 29, 2016
Investment Income, Net [Abstract]        
Interest income on corporate funds $ 2.4 $ 2.1 $ 7.2 $ 6.1
Interest expense (0.6) (0.2) (1.9) (0.7)
Net loss from equity-method investments (0.6) (0.2) (1.7) (0.7)
Investment income, net $ 1.2 $ 1.7 $ 3.6 $ 4.7