Quarterly report pursuant to Section 13 or 15(d)

Stock Options - Range of Expected Volatilities for Options (Detail)

v2.4.0.8
Stock Options - Range of Expected Volatilities for Options (Detail) (Service-Based Vesting Condition Options [Member])
3 Months Ended
Feb. 28, 2013
Service-Based Vesting Condition Options [Member]
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Minimum expected volatility 112.90%
Maximum expected volatility 114.90%