Debt (Details) - Schedule of debt (USD $) In Millions, unless otherwise specified	Nov. 30, 2013	May 31, 2013	Nov. 30, 2012
Debt (Details) - Schedule of debt [Line Items]
Debt Long Term And Short Term Outstanding, Carrying Value	$ 9.6	$ 2.0	$ 153.6
Debt Long Term And Short Term Outstanding, Fair Value	9.6	2.0	155.8
Less lines of credit, short-term debt and current portion of long-term debt	(9.6)	(2.0)	(0.7)
Less lines of credit, short-term debt and current portion of long-term debt	(9.6)	(2.0)	(0.7)
Total long-term debt			152.9
Total long-term debt			155.1
Line of Credit [Member]
Debt (Details) - Schedule of debt [Line Items]
Debt Long Term And Short Term Outstanding, Carrying Value	9.6	2.0	0.7
Debt Long Term And Short Term Outstanding, Fair Value	9.6	2.0	0.7
Notes Due 2013 [Member]
Debt (Details) - Schedule of debt [Line Items]
Debt Long Term And Short Term Outstanding, Carrying Value			152.9
Debt Long Term And Short Term Outstanding, Fair Value			$ 155.1