Annual report pursuant to Section 13 and 15(d)

Note 7 - Note Payable (Details Textual)

v3.20.4
Note 7 - Note Payable (Details Textual) - USD ($)
 12 Months Ended
Nov. 12, 2019
Dec. 29, 2017
May 22, 2017
Dec. 31, 2020
Dec. 31, 2019
Nov. 26, 2019
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)         2,473,785  
Debt Conversion, Converted Instrument, Amount       $ 35,529,000  
Notes Payable, Noncurrent, Total       4,518,000 3,983,000  
Warrants and Rights Outstanding         3,502,000  
Gains (Losses) on Restructuring of Debt       $ (6,705,000)  
Series B Preferred Stock [Member]            
Conversion of Stock, Conversion Rate (in dollars per share)       $ 15.30    
Preferred Stock, Fair Value, Per Share (in dollars per share)           $ 1,023.23
Convertible Preferred Stock, Fair Value           $ 32,027,000
Series B Convertible Preferred Stock Into Common Stock [Member] | Minimum [Member]            
Conversion of Stock, Conversion Rate (in dollars per share) $ 15.30          
Series B Convertible Preferred Stock Into Common Stock [Member] | Maximum [Member]            
Conversion of Stock, Conversion Rate (in dollars per share) $ 18.36          
Conversion of Term Loan with CRG Into Stock and Warrants [Member]            
Debt Conversion, Original Debt, Amount $ 28,981,000          
Debt Conversion, Converted Instrument, Amount $ 31,300,000          
Conversion of Term Loan with CRG Into Series B Convertible Preferred Stock [Member]            
Debt Conversion, Converted Instrument, Shares Issued (in shares) 31,300          
May 2017 Issuance Related to 2017 Loan Agreement [Member]            
Warrants and Rights Outstanding, Term (Year)     10 years      
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)     223   223  
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)     $ 9,500   $ 9,500  
Warrants and Rights Outstanding     $ 940,000      
Warrants Issued Upon Conversion of Term Loan with CRG [Member]            
Warrants and Rights Outstanding, Term (Year) 5 years          
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) 989,379       741,940  
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)         $ 15.50  
Class of Warrants and Rights Outstanding, Exercise Price Percentage of Conversion Rate 120.00%          
Warrants and Rights Outstanding $ 3,502,000          
The 2017 Loan Agreement [Member]            
Notes Payable, Noncurrent, Total       $ 4,518,000    
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      
Proceeds from Lines of Credit, Total   $ 10,000,000        
Debt Instrument, Term (Year)     6 years      
Debt instrument, Interest Only Payment, Period (Year)     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       532,000 $ 1,226,000  
Debt Instrument, Prepayment Fee, Percentage     5.00%      
Debt Instrument, Back-end Facility Fee Percentage of Principal 25.00%   5.00%      
Notes Payable, Noncurrent, Total       $ 4,518,000 $ 3,983,000