Annual report pursuant to Section 13 and 15(d)

Term Loan Agreements and Long Term Debt - Term Loan Agreement and Revolving Loan (Details)

v3.8.0.1
Term Loan Agreements and Long Term Debt - Term Loan Agreement and Revolving Loan (Details)
 12 Months Ended
Oct. 26, 2016
Oct. 25, 2016
USD ($)
item
Dec. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Debt Instrument [Line Items]          
Exit fee percent   5.00%      
Debt issuance costs     $ 29,472 $ 800,847 $ 180,139
Three Peaks Loan          
Debt Instrument [Line Items]          
Payments of Debt Extinguishment Costs   $ 2,300,000      
MidCap Loan          
Debt Instrument [Line Items]          
Proceeds from issuance of debt   25,000,000      
Debt issuance costs   800,000      
Term Loan Agreement | MidCap Loan          
Debt Instrument [Line Items]          
Face amount   $ 21,000,000 $ 21,000,000 $ 21,000,000  
Number of months requiring principal and interest payments | item   30      
Interest payable, percent   8.00% 8.00% 8.00%  
Interest rate spread   0.50% 0.50% 0.50%  
Effective interest rate (as a percent)     9.36% 9.36%  
Annual agency fee, percent of aggregate principal amount   (0.25%)      
Minimum prepayment amount   $ 2,500,000      
Integral multiple of the minimum prepayment amount   $ 1,000,000      
Maximum number of partial voluntary prepayments allowed | item   3      
Prepayment fee percent, year one   3.00%      
Prepayment fee percent, year two   2.00%      
Prepayment fee percent, thereafter   1.00%      
Revolver Loan Agreement | MidCap Loan          
Debt Instrument [Line Items]          
Interest payable, percent   4.50% 4.50% 4.50%  
Interest rate spread   0.50% 0.50% 0.50%  
Effective interest rate (as a percent)     5.86% 5.86%  
Prepayment fee percent, year one 3.00%        
Prepayment fee percent, year two 2.00%        
Prepayment fee percent, thereafter 1.00%        
Percent of Borrowing Base which accrues interest   30.00%      
Maximum line of credit amount   $ 10,000,000 $ 10,000,000 $ 10,000,000  
Borrowing amount available   $ 7,700,000 $ 4,000,000    
Collateral management fee, percent   (0.50%)      
Unused line fee, percent   0.50%      
Revolver Loan Agreement | MidCap Loan | Maximum          
Debt Instrument [Line Items]          
Maximum line of credit amount   $ 15,000,000