CONVERTIBLE SENIOR NOTES (Tables)
 12 Months Ended
Dec. 31, 2013
CONVERTIBLE SENIOR NOTES [Abstract]  
Schedule of carrying amounts of the liability and equity components of the convertible notes
The following tables provide additional information about the Company’s 2010 Notes.

 
 
December 31, 2013
  
December 31,2012
 
Carrying amount of the equity component (additional paid-in capital)
 
$
24,375
  
$
24,375
 
Principal amount of the 2010 Notes
  
125,000
   
125,000
 
Unamortized discount of the liability component
  
9,119
   
14,082
 
Net carrying amount of the liability component
  
115,881
   
110,918
 
Schedule of effective interest rate, cash and non-cash interest expense and deferred financing cost amortization

 
 
Years Ended December 31,
 
 
 
2013
  
2012
  
2011
 
Effective interest rate on liability component
  
10.0
%
  
10.0
%
  
10.0
%
Cash interest expense recognized
 
$
6,250
  
$
6,263
  
$
6,231
 
Non-cash interest expense recognized
  
4,963
   
4,537
   
4,072
 
Non-cash deferred financing amortization costs included in interest expense
  
720
   
722
   
720