Quarterly report pursuant to Section 13 or 15(d)

Note 6 - Note Payable (Details Textual)

v3.10.0.1
Note 6 - Note Payable (Details Textual) - USD ($)
3 Months Ended 9 Months Ended
May 22, 2017
Jun. 20, 2016
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Class of Warrant or Right, Number of Securities Called by Warrants or Rights     642,622   642,622  
Interest Payable     $ 17,131,000   $ 17,131,000  
June 2016 Issuance Related to 2016 Loan Agreement [Member]            
Warrant Term   10 years        
Class of Warrant or Right, Number of Securities Called by Warrants or Rights   100,402 100,402   100,402  
Class of Warrant or Right, Exercise Price of Warrants or Rights   $ 4.98 $ 4.98   $ 4.98  
May 2017 Issuance Related to 2017 Loan Agreement [Member]            
Class of Warrant or Right, Number of Securities Called by Warrants or Rights 222,049   222,049   222,049  
Class of Warrant or Right, Exercise Price of Warrants or Rights $ 9.50   $ 9.50   $ 9.50  
Warrants and Rights Outstanding, Term 10 years          
The 2016 Loan Agreement [Member] | Western Alliance Bank [Member]            
Debt Instrument, Face Amount   $ 10,000,000        
Debt Instrument, Fee, Percentage   4.00%        
The 2016 Loan Agreement [Member] | Western Alliance Bank [Member] | First Tranche [Member]            
Proceeds from Issuance of Long-term Debt, Total   $ 7,500,000        
The 2016 Loan Agreement [Member] | Western Alliance Bank [Member] | Second Tranche [Member]            
Proceeds from Issuance of Long-term Debt, Total   $ 2,500,000        
The 2017 Loan Agreement [Member] | CRG LP [Member]            
Debt Instrument, Face Amount $ 20,000,000          
Debt Agreement, Covenant, Additional Funding 10,000,000          
Debt Agreement, Maximum Borrowing Capacity $ 30,000,000          
Debt Instrument, Term 6 years          
Debt instrument, Interest Only Payment, Period 4 years          
Debt Instrument, Interest Rate, Stated Percentage 12.50%          
Debt Instrument, Interest Rate, Stated Percentage Deferred During Interest-only Period 4.00%          
Paid-in-Kind Interest     $ 318,000 $ 205,262 $ 934,000 $ 285,000
Debt Instrument, Prepayment Fee, Percentage 5.00%          
Debt Instrument, Prepayment Fee, Period of Term 5 years          
Debt Instrument, Covenant, Cash and Cash Equivalents $ 2,000,000          
The 2017 Loan Agreement [Member] | CRG LP [Member] | Other Noncurrent Liabilities [Member]            
Interest Payable     $ 394,000   $ 394,000