v2.3.0.11
Equity Compensation Plans (Fair Value Of Stock Options Granted, Estimated Using Weighted-Average Assumptions) (Details)
12 Months Ended
May 31, 2011
Equity Compensation Plans  
Risk-free interest rate 1.70%
Expected dividend yield 0.00%
Expected stock price volatility 38.80%
Expected option life (in years) 4.0