Share-based Compensation (Tables)
 12 Months Ended
Dec. 31, 2013
Assumption Used to Estimate Fair Value of Stock Awards Granted

The assumptions used to estimate the fair value of stock awards granted in the years ended December 31, 2013, 2012 and 2011 are as follows:

 

     Year Ended December 31,  
         2013             2012             2011      

Volatility

      44.4 %      40.1 %      34.6 % 

Expected term (years)

      8        10        10   

Risk free interest rate

      2.0 %      2.1 %      2.7 % 

Expected dividend yield

      0 %      0 %      0 % 
Stock Option Activity

A summary of stock option activity during 2013 is presented below:

 

Options

    Shares     Weighted-Average
Exercise Price		      Weighted-Average
Remaining
Contractual
Term (Years)		  

Outstanding December 31, 2012

      399      $ 41.80      

Granted

      74        32.10      

Exercised

      —          —        

Forfeited, canceled, or expired

      (157 )      42.10      
  

 

 

       

Outstanding December 31, 2013

      316      $ 39.40         6.5   
  

 

 

       

Exercisable at December 31, 2013

      184      $ 42.30         2.6   
  

 

 

       
Non-Vested Shares of Restricted Common Stock

A summary of non-vested restricted common stock activity is presented below:

 

Non-Vested Restricted Stock

        Shares         Weighted-Average
Grant-Date
Fair Value		  

Non-vested at December 31, 2012

      87      $ 51.30   

Granted

      41        15.82   

Vested

      (25 )      52.87   

Forfeited

      (10 )      47.43   
  

 

 

    

Non-vested at December 31, 2013

      93      $ 35.64   
  

 

 

    
Non-Vested Shares of Restricted Common Stock

A summary of non-vested restricted common stock activity is presented below:

 

Non-Vested Restricted Stock Units

        Shares         Weighted-Average
Grant-Date
Fair Value		  

Non-vested at December 31, 2012

      —        $ —     

Granted

      62        34.40   

Vested

      —          —     

Forfeited

      (6 )      36.30   
  

 

 

    

Non-vested at December 31, 2013

      56      $ 35.64