XML 33 R28.htm IDEA: XBRL DOCUMENT v2.4.0.6
Stockholders' Equity (Tables)
9 Months Ended
Sep. 30, 2012
Stockholders' Equity [Abstract]  
Fair value of the warrants

The fair value of the warrants at September 30, 2012, and December 31, 2011, consisted of the following (in thousands):

 

                 
    September 30,     December 31,  
    2012     2011  

2009 Warrants

  $ 2,712     $ 3,010  

2010 Warrants

    5,164       4,969  
   

 

 

   

 

 

 

Total warrant liability

  $ 7,876     $ 7,979  
   

 

 

   

 

 

 
Fair value assumptions of warrants

The fair value of the Company’s warrants was based on using the binomial-lattice option valuation model and using the following assumptions at September 30, 2012, and December 31, 2011:

 

                 
    September 30,     December 31,  
    2012     2011  

2009 Warrants:

               

Expected term (in years)

    1.90       2.65  

Estimated volatility

    50     74

Risk-free interest rate

    0.23     0.36

Expected dividend yield

    0     0

2010 Warrants:

               

Expected term (in years)

    3.11       3.86  

Estimated volatility

    58     70

Risk-free interest rate

    0.31     0.60

Expected dividend yield

    0     0