XML 48 R56.htm IDEA: XBRL DOCUMENT v2.4.0.8
Warrants (Fair Value of Warrants is Estimated Using Black-Scholes Option Pricing Model) (Detail) (USD $)
 12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
September 2013 Warrant [Member]
    
Class of Warrant or Right [Line Items]    
Strike price $ 2.50 $ 0
Expected term (years) 4 years 8 months 19 days 0 years
Volatility % 71.97% 0.00%
Risk-free rate % 1.61% 0.00%
December 2012 Warrants [Member]
    
Class of Warrant or Right [Line Items]    
Strike price $ 1.90 $ 1.90
Expected term (years) 3 years 11 months 23 days 4 years 11 months 23 days
Volatility % 71.38% 80.93%
Risk-free rate % 1.25% 0.72%
April 2011 Warrants [Member]
    
Class of Warrant or Right [Line Items]    
Strike price $ 0.65 $ 0.65
Expected term (years) 3 years 3 months 22 days 4 years 3 months 18 days
Volatility % 71.71% 82.48%
Risk-free rate % 0.93% 0.59%
March 2011 Warrants [Member]
    
Class of Warrant or Right [Line Items]    
Strike price $ 0.65 $ 0.65
Expected term (years) 2 years 2 months 5 days 3 years 2 months 5 days
Volatility % 73.45% 69.90%
Risk-free rate % 0.45% 0.39%
March 2010 Warrants [Member]
    
Class of Warrant or Right [Line Items]    
Strike price $ 2.15 $ 2.18
Expected term (years) 2 years 2 months 27 days 3 years 2 months 27 days
Volatility % 73.36% 69.79%
Risk-free rate % 0.47% 0.40%
August 2009 Warrants [Member]
    
Class of Warrant or Right [Line Items]    
Strike price $ 4.50 $ 4.50
Expected term (years) 7 months 2 days 1 year 7 months 2 days
Volatility % 66.85% 74.13%
Risk-free rate % 0.11% 0.21%