Annual report pursuant to Section 13 and 15(d)

Note 7 - Note Payable (Details Textual)

v3.19.1
Note 7 - Note Payable (Details Textual) - USD ($)
12 Months Ended
May 22, 2017
Jun. 20, 2016
Dec. 31, 2018
Dec. 31, 2017
Class of Warrant or Right, Number of Securities Called by Warrants or Rights     642,622  
Interest Payable     $ 16,127,000  
Notes Payable, Noncurrent, Total     $ 30,528,000 $ 28,948,000
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  
Class of Warrant or Right, Exercise Price of Warrants or Rights   $ 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  
Class of Warrant or Right, Exercise Price of Warrants or Rights $ 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     $ 1,256,000 495,000
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      
Notes Payable, Noncurrent, Total     30,528,000 $ 28,948,000
The 2017 Loan Agreement [Member] | CRG LP [Member] | Other Noncurrent Liabilities [Member]        
Interest Payable     $ 484,000