Notes Payable (Tables)
 12 Months Ended
Dec. 31, 2016
Debt Disclosure [Abstract]  
Schedule of Notes Payable

As of December 31, 2016 and 2015, notes payable consist of the following:

 

     December 31,  
     2016  
     (in thousands)  

Notes payable

      3,183  

Debt discount, net of accretion

      (9 ) 

Accretion related to final payment

      415  
  

 

 

  

Notes payable, net of discount, short term

    $ 3,589  
  

 

 

  

 

     December 31,  
     2015  
     (in thousands)  

Notes payable

    $ 6,119  

Less: current portion

      (2,936 ) 
  

 

 

  

Notes payable, net of current portion

      3,183  

Debt discount, net of accretion

      (36 ) 

Accretion related to final payment

      306  
  

 

 

  

Notes payable, net of discount, long term

    $ 3,453  
  

 

 

  
Schedule of Estimated Future Principal Payments

As of December 31, 2016, the estimated future principal payments due are as follows:

 

Years Ending December 31,

       
(in thousands)       

2017

    $ 3,183  
  

 

 

  

Total

    $ 3,183