Other Accrued Expenses - Schedule of accrued expenses (Details) - USD ($) $ in Millions	Feb. 28, 2018	May 31, 2017	Feb. 28, 2017
Schedule of accrued expenses [Abstract]
Accrued payroll, payroll taxes and benefits	$ 44.8	$ 48.5	$ 45.0
Accrued bonus and commissions	19.9	33.8	20.1
Accrued other taxes	23.4	26.1	24.7
Accrued advertising and promotions	35.8	34.9	34.9
Accrued insurance	8.1	7.6	8.1
Other accrued expenses	30.6	27.1	29.0
Total accrued expenses	$ 162.6	$ 178.0	$ 161.8