Goodwill and Other Intangibles (Detail) - Schedule of other intangible assets subject to amortization (USD $) In Millions, unless otherwise specified	9 Months Ended		12 Months Ended
	Feb. 29, 2012	Feb. 28, 2011	May 31, 2011
Beginning balance	$ 18.0
Amortization expense	1.3	1.0	1.4
Total other intangibles subject to amortization	16.2	18.4	18.0
Customer Lists [Member]
Beginning balance	0.7	0.8	0.8
Amortization expense	(0.2)	(0.2)	(0.2)
Foreign currency translation	0	0.1	0.1
Total other intangibles subject to amortization	0.5	0.7	0.7
Other Intangible Assets [Member]
Beginning balance	17.3	2.2	2.2
Additions due to acquisition		5.6	5.6
Reclassified from indefinite-lived intangible assets		10.7	10.7
Impairment charge	(0.5)
Amortization expense	(1.1)	(0.8)	(1.2)
Total other intangibles subject to amortization	$ 15.7	$ 17.7	$ 17.3