Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Financial Instruments (Details Textual) (Details)

v2.4.0.6
Fair Value of Financial Instruments (Details Textual) (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 12 Months Ended
May 31, 2012
May 31, 2012
Fair Value of Financial Instruments [Abstract]    
Decrease in AFS debt securities sensitivity $ (0.8) $ (0.8)
Increase in AFS debt securities sensitivity $ 0.9 $ 0.9
Change in unobservable inputs, higher 100 basis points higher  
Global high yield B, Maximum   7.63%
Change in unobservable inputs, lower 100 basis points lower  
Global high yield B, Minimum   5.23%
Australian risk free interest rate, Maximum   4.75%
Australian risk free interest rate, Minimum   3.75%
Global high yield B interest rate 7.63% 7.63%
Australian risk free interest rate 3.75% 3.75%