Weighted Average Estimated Fair Value of Warrant Issued (Detail)
9 Months Ended
Sep. 30, 2012
Warrant Issue Price $0.62 Per Share [Member]
 
Debt Instrument [Line Items]  
Expected volatility 128.00%
Risk-free interest rate 0.31%
Expected life 2 years
Dividend yield 0.00%
Warrant Issue Price $0.81 Per Share [Member]
 
Debt Instrument [Line Items]  
Expected volatility 133.00%
Risk-free interest rate 0.36%
Expected life 3 years
Dividend yield 0.00%