Goodwill and Other Intangibles (Details) - Schedule of activity in goodwill - USD ($) $ in Millions	12 Months Ended
	May 31, 2018	May 31, 2017
Goodwill [Roll Forward]
Gross beginning balance	$ 158.5	$ 155.8
Accumulated impairment	(39.6)	(39.6)
Beginning balance	118.9	116.2
Additions	0.0	2.8
Foreign currency translation	0.2	(0.1)
Other	0.1	0.0
Gross ending balance		158.5
Accumulated impairment		(39.6)
Ending balance	$ 119.2	$ 118.9