Income Taxes (Tables)
 12 Months Ended
Dec. 31, 2016
Income Tax Disclosure [Abstract]  
Schedule of Reconciliation of Federal Statutory Income Tax Rate to Effective Tax Rate

A reconciliation of the Federal statutory income tax rate to our effective tax rate is as follows:

 

     Percent of Income
before Income Taxes		  
     2016     2015  

Statutory Federal income tax rate

      34.0 %      34.0 % 

State income taxes - net of Federal tax benefit

      0.8 %      1.5 % 

Other permanent differences

      (8.1 %)      (3.5 )% 

Valuation allowances

      (37.0 %)      (40.2 %) 

Research and development - U.S.

      10.3 %      8.2 % 

Research and development - Foreign

      0.2 %      0.2 % 
  

 

 

    

 

 

  

Effective tax rate for the year

      0.2 %      0.2 % 
  

 

 

    

 

 

  
Components of Deferred Tax Assets

Significant components of our deferred tax assets are as follows (in thousands):

 

     December 31,  
     2016      2015  

Net operating loss carryforwards

    $ 44,929      $ 40,215  

Research and development credit carryforwards

      6,017        4,454  

Compensation expense

      2,735        3,300  

Other

      1,266        1,129  
  

 

 

     

 

 

  

Total deferred tax assets

      54,947        49,098  

Valuation allowance for deferred tax assets

      (54,772 )       (48,921 ) 
  

 

 

     

 

 

  

Net deferred tax assets

    $ 175      $ 177