XML 94 R38.htm IDEA: XBRL DOCUMENT v2.4.0.8
Stock-Based Compensation (Tables)
 12 Months Ended
Dec. 31, 2013
Stock-Based Compensation  
Summary of the activity related to the shares of common stock covered by outstanding options under the plans
 
   Number of
Shares		   Weighted Average
Exercise Price		   Remaining
Contractual Term
(in years)		   Aggregate
Intrinsic value		  

Balance at December 31, 2012

     5,579,042   $ 6.68              

Granted

     1,654,315     1.64              

Exercised

     (7,550 )   1.82              

Forfeited

     (670,291 )   2.11              

Expired

     (354,087 )   9.26              
                         
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Balance at December 31, 2013

     6,201,429     5.68     6.09   $ —  
                         
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
                         

Vested and expected to vest at December 31, 2013

     6,009,973     5.79     6.04     —  

Exercisable at December 31, 2013

     3,913,834     7.49     5.18     —  
Summary of information about the shares of common stock covered by outstanding and exercisable options under the plans

A summary of information about the shares of common stock covered by outstanding and exercisable options under the Plans at December 31, 2013 follows:

 
   Stock Options Outstanding   Stock Options Exercisable  
Range of
exercise prices
  Number
of shares		   Weighted
average
remaining
contractual life
(in years)		   Weighted
average
exercise price
per share		   Number of
shares		   Weighted
average
exercise price
per share		  
$1.27 - 1.48     240,400     9.65   $ 1.41     15,610   $ 1.40  
1.55 - 1.55     1,045,000     7.56     1.55     600,000     1.55  
1.56 - 1.69     1,038,479     6.69     1.68     358,018     1.66  
1.74 - 2.46     360,014     7.41     2.09     190,189     2.11  
2.66 - 2.66     866,949     6.60     2.66     380,256     2.66  
2.72 - 7.25     737,997     5.15     5.98     561,599     6.12  
7.31 - 9.77     668,092     5.26     8.95     602,927     8.93  
10.08 - 14.49     872,086     4.07     12.49     832,823     12.42  
14.53 - 23.99     342,412     3.72     18.86     342,412     18.86  
24.97 - 24.97     30,000     3.39     24.97     30,000     24.97  
                             
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
      6,201,429     6.09     5.68     3,913,834     7.49  
                             
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
                             
Schedule of assumptions used in determining fair value of stock options granted using the Black-Scholes option pricing model
 
   Year Ended December 31,
 
   2013   2012   2011

Expected dividend yield

   —   —   —

Risk-free rate

   0.71% - 2.05%   0.67% - 1.15%   0.88% - 2.38%

Expected option term (in years)

   6.0 - 6.1   5.3 - 5.5   5.5 - 5.6

Volatility

   84% - 85%   84% - 87%   77% - 80%