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           Stock Options - Fair Value of Options Granted (Detail) 
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        3 Months Ended | 6 Months Ended | ||
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           May 31, 2013 
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           May 31, 2012 
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           May 31, 2013 
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           May 31, 2012 
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           Service-Based Vesting Condition Options [Member] 
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| Weighted average values: | ||||
| Expected dividends | 0.00% | 0.00% | 0.00% | 0.00% | 
| Expected volatility | 112.40% | 113.70% | 113.30% | 111.80% | 
| Risk free interest rate | 0.81% | 0.92% | 0.81% | 0.93% | 
| Expected life | 5 years | 5 years | 5 years | 5 years 8 months 12 days | 
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           Performance and Market-Based Vesting Condition Options [Member] 
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| Weighted average values: | ||||
| Expected dividends | 0.00% | 0.00% | ||
| Expected volatility | 113.50% | 112.40% | ||
| Risk free interest rate | 0.87% | 0.90% | ||
| Expected life | 5 years | 5 years 6 months | ||
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- Details 
          
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- Definition 
          Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price). Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Risk-free interest rate assumption used in valuing an instrument. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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