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Stock-Based Compensation - Weighted-average Black-Scholes assumptions (Details)
12 Months Ended
Feb. 28, 2013
Feb. 29, 2012
Expected life (in years)   4 years
Risk free interest rate, minimum 0.35% 0.71%
Risk free interest rate, maximum 0.37% 1.17%
Expected volatility, minimum 88.50% 29.00%
Expected volatility, maximum 88.50% 31.00%
Expected dividend yield 0.00% 0.00%
Minimum
   
Expected life (in years) 3 years  
Maximum
   
Expected life (in years) 8 years