Other Accrued Expenses - Schedule of accrued expenses (Details) - USD ($) $ in Millions	Aug. 31, 2017	May 31, 2017	Aug. 31, 2016
Schedule of accrued expenses [Abstract]
Accrued payroll, payroll taxes and benefits	$ 46.3	$ 48.5	$ 42.9
Accrued bonus and commissions	13.3	33.8	13.1
Accrued other taxes	21.5	26.1	25.4
Accrued advertising and promotions	31.9	34.9	31.9
Accrued insurance	7.5	7.6	8.0
Other accrued expenses	32.8	27.1	30.3
Total accrued expenses	$ 153.3	$ 178.0	$ 151.6