Annual report pursuant to Section 13 and 15(d)

Long-Term Debt and Other Financings - General Electric Capital Corporation Term Loan - Additional Information (Details)

v3.3.1.900
Long-Term Debt and Other Financings - General Electric Capital Corporation Term Loan - Additional Information (Details)
 1 Months Ended 12 Months Ended
Feb. 27, 2015
USD ($)
$ / shares
shares
Sep. 27, 2012
USD ($)
$ / shares
shares
Sep. 30, 2012
USD ($)
Installment
Dec. 31, 2011
USD ($)
$ / shares
shares
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
Dec. 31, 2013
USD ($)
Debt Instrument [Line Items]              
Repayment of principal         $ 6,128,000 $ 5,917,000 $ 3,125,000
Loss on extinguishment of debt         (429,000)    
GECC Term Loan [Member]              
Debt Instrument [Line Items]              
Outstanding principal balance     $ 3,100,000 $ 10,000,000   $ 5,200,000  
Aggregate number of unregistered shares of common stock called by warrants (in shares) | shares   39,346   263,158      
Exercise price of warrants (in dollars per share) | $ / shares   $ 3.54   $ 1.14      
Exercisable period of warrants   5 years   5 years      
Warrants expiration period   2017-09   2016-12      
Increase in term loan obligation     4,600,000        
Amended balance of the term loan     $ 12,500,000        
Fixed interest rate accrued (in hundredths)     10.90%        
Periodic Payment, Principal     $ 347,222        
Number of monthly installments | Installment     27        
Debt issuance costs     $ 200,000        
Final payment fee     $ 875,000 $ 500,000      
Estimated fair value of warrants   $ 100,000   $ 200,000      
Prepayment premium year one (in hundredths)     3.00%        
Prepayment premium year two (in hundredths)     2.00%        
Prepayment premium year thereafter (in hundredths)     1.00%        
Accrued final payment fee   $ 200,000          
Repayment of principal $ 5,500,000            
Loss on extinguishment of debt         (400,000)    
Hercules Loan [Member]              
Debt Instrument [Line Items]              
Outstanding principal balance         $ 20,000,000    
Aggregate number of unregistered shares of common stock called by warrants (in shares) | shares 181,268            
Exercise price of warrants (in dollars per share) | $ / shares $ 3.31            
Exercisable period of warrants 5 years            
Warrants expiration period 2020-02            
Debt issuance costs $ 500,000            
Final payment fee 1,200,000            
Estimated fair value of warrants 500,000            
Proceeds from loans $ 20,000,000