Share-Based Compensation (Tables)
 12 Months Ended
Dec. 31, 2013
Variables Used in Black-Scholes Option Pricing Model to Determine Estimated Grant Date Fair Value for Options Granted

The following are the variables used in the Black-Scholes option pricing model to determine the estimated grant date fair value for options granted under the Company’s incentive plans for each of the years presented:

 

     2013    2012    2011

Expected volatility

    83% - 104%    76% - 87%    74% - 88%

Weighted-average volatility

    93%    80%    81%

Expected dividends

    —  %    —  %    —  %

Expected term (in years)

    3.8 – 6.6    5.0 - 6.6    5.0 - 6.7

Risk-free rate

    0.68% - 2.45%    0.57% - 1.26%    1.17% - 2.24%
Summary of Options Activity Under Incentive Plans

The table below presents a summary of our option activity as of December 31, 2013 and changes during the year then ended:

 

     Shares      Weighted-
Average
Exercise
Price		      Weighted-
Average
Remaining
Contractual
Term
(Yrs)		      Aggregate
Intrinsic
Value		  

Outstanding at January 1, 2013

      1,825,320        $ 1.88         

Granted

      928,000          1.57         

Exercised

      (117,030)         1.00         

Forfeited or expired

      (341,080)         1.08         
  

 

 

           

Outstanding at December 31, 2013

      2,295,210        $ 1.51         5.0       $ 3,468,464  
  

 

 

     

 

 

     

 

 

     

 

 

  

Exercisable at December 31, 2013

      609,090        $ 2.00         2.6       $ 621,573