Goodwill and Other Intangibles (Details) - Schedule of activity in goodwill - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Aug. 31, 2015	Aug. 31, 2014	May. 31, 2014
Goodwill [Roll Forward]
Gross beginning balance	$ 155.9	$ 156.0
Accumulated impairment	(39.6)	(34.2)
Beginning balance	116.3	121.8
Impairment charge	0.0	0.0	$ (5.4)
Foreign currency translation	(0.1)	0.0	(0.1)
Gross ending balance	155.8	156.0	156.0
Accumulated impairment	(39.6)	(34.2)	(34.2)
Ending balance	$ 116.2	$ 121.8	$ 121.8