Annual report pursuant to Section 13 and 15(d)

Stock-Based Employee Compensation (Details 6)

v2.4.0.6
Stock-Based Employee Compensation (Details 6) (Employee Stock [Member])
12 Months Ended
Feb. 28, 2013
Feb. 29, 2012
Feb. 28, 2011
Employee Stock [Member]
     
Weighted average assumptions to estimate fair value of equity instruments using Black-Scholes option-pricing model      
Expected life 0 years 6 months 0 years 6 months 0 years 6 months
Expected volatility 41.70% 30.40% 25.80%
Risk-free interest rate 0.10% 0.20% 0.20%
Expected dividend yield 0.00% 0.00% 0.00%