Comprehensive Income (Loss) (Detail) - Schedule of comprehensive income (loss) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 29, 2012	Feb. 28, 2011	Feb. 29, 2012	Feb. 28, 2011
Net income (loss)	$ (10.3)	$ (25.1)	$ 45.4	$ 14.6
Other comprehensive income (loss), net:
Foreign currency translation adjustment	3.7	4.3	(2.2)	12.5
Pension and post-retirement adjustments	0.9	0.7	3.7	5.3
Total other comprehensive income (loss), net:	4.6	5.0	1.5	17.8
Total comprehensive income (loss)	$ (5.7)	$ (20.1)	$ 46.9	$ 32.4