Income Taxes (Tables)
 12 Months Ended
Dec. 31, 2015
Income Tax Disclosure [Abstract]  
Reconciliation of Federal Statutory Income Tax Rate

Reconciliation of the Federal statutory income tax rate of 34% to the effective rate is as follows:

 

     2015     2014     2013  

Federal statutory income tax rate

      34.00 %      34.00 %      34.00 % 

State taxes, net of federal benefit

      3.45        3.45        3.45   

Permanent differences-derivative loss (gain)

      —          (9.10 )      0.11   

Permanent differences-other

      (4.66 )      2.24        (1.07 ) 

Research and development (“R&D”) credit

      0.95        2.73        4.91   

Other

      0.64        0.61        0.64   

Increase in valuation allowance

      (34.38 )      (33.93 )      (42.04 ) 
  

 

 

    

 

 

    

 

 

  
     0.00 %      0.00 %      0.00 % 
  

 

 

    

 

 

    

 

 

  

Significant Components of Deferred Tax Assets and Liabilities

The tax effects of temporary differences and net operating losses that give rise to significant components of deferred tax assets and liabilities consist of the following:

 

     December 31,  

Deferred tax assets (liabilities)

    2015      2014  

Deferred revenue

    $ 7,490       $ 315   

Basis difference in equipment

      (1,013 )       (975 ) 

Basis difference in intangibles

      1,122         1,102   

Accrued liabilities and other

      1,563         360   

R&D credit

      11,138         11,316   

Stock options

      1,151         462   

Net operating loss carry-forward

      63,509         59,481   
  

 

 

     

 

 

  
     84,960         72,061   
  

 

 

     

 

 

  

Less: valuation allowance

      (84,960 )       (72,061 ) 
  

 

 

     

 

 

  
   $ —        $ —