Assumptions used to Value Warrants (Detail) (USD $)
|
3 Months Ended | |||||
---|---|---|---|---|---|---|
Sep. 30, 2012
Y
|
Jun. 30, 2012
Y
|
|||||
Warrants issued on December 20, 2007
|
||||||
Class of Warrant or Right [Line Items] | ||||||
Estimated life in years | 0.25 | 0.50 | ||||
Risk-free interest rate | 0.09% | [1] | 0.15% | [1] | ||
Volatility | 72.00% | 75.00% | ||||
Dividend paid | ||||||
Warrants issued on December 20, 2007 | Minimum
|
||||||
Class of Warrant or Right [Line Items] | ||||||
Estimated probabilities | 10.00% | 10.00% | ||||
Estimated strike prices | $ 0.32 | $ 0.33 | ||||
Warrants issued on December 20, 2007 | Maximum
|
||||||
Class of Warrant or Right [Line Items] | ||||||
Estimated probabilities | 50.00% | 50.00% | ||||
Estimated strike prices | $ 0.35 | $ 0.36 | ||||
Warrants issued on June 30, 2008
|
||||||
Class of Warrant or Right [Line Items] | ||||||
Estimated life in years | 0.75 | 1.00 | ||||
Risk-free interest rate | 0.15% | [1] | 0.21% | [1] | ||
Volatility | 72.00% | 75.00% | ||||
Dividend paid | ||||||
Warrants issued on June 30, 2008 | Minimum
|
||||||
Class of Warrant or Right [Line Items] | ||||||
Estimated probabilities | 10.00% | 10.00% | ||||
Estimated strike prices | $ 0.32 | $ 0.33 | ||||
Warrants issued on June 30, 2008 | Maximum
|
||||||
Class of Warrant or Right [Line Items] | ||||||
Estimated probabilities | 50.00% | 50.00% | ||||
Estimated strike prices | $ 0.35 | $ 0.36 | ||||
Warrants issued on April 1, 2010
|
||||||
Class of Warrant or Right [Line Items] | ||||||
Estimated life in years | 2.50 | 2.75 | ||||
Risk-free interest rate | 0.30% | [1] | 0.39% | [1] | ||
Volatility | 75.00% | 78.00% | ||||
Dividend paid | ||||||
Estimated probabilities | 15.00% | 15.00% | ||||
|