Annual report pursuant to Section 13 and 15(d)

Notes Payable (Narrative) (Details)

v3.21.1
Notes Payable (Narrative) (Details)
12 Months Ended
Sep. 30, 2020
USD ($)
Mar. 29, 2019
USD ($)
item
installment
$ / shares
shares
Dec. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
Debt Instrument [Line Items]        
Interest expense     $ 3,917,000 $ 1,767,000
Horizon Notes [Member]        
Debt Instrument [Line Items]        
Debt instrument face value $ 15,000,000.0 $ 20,000,000.0    
Proceeds from Horizon Notes   15,000,000.0    
Loan agreement, unused borrowing capacity   5,000,000.0    
Repayment of debt, amount 15,000,000.0      
Accrued and unpaid interest 112,500      
Debt instrument, fee 750,000 200,000    
Debt instrument, prepayment penalties 550,000      
Legal fees   30,000    
Debt instrument legal and other direct costs   $ 1,200,000    
Maturity of each advance   42 months    
Number of advances | item   3    
Debt interest rate (as a percent)   9.00% 9.00% 9.00%
Number of monthly installments | installment   18    
Prepayment charge threshold   $ 500,000    
Prepayment charge (as a percent)   4.00%    
Prepayment charge, second period (as a percent)   3.00%    
Prepayment charge, thereafter (as a percent)   2.00%    
Final payment fee per advance   $ 250,000    
Final payment fee   750,000 $ 750,000  
Default threshold   $ 250,000    
Minimum monthly cash balance, range     13,000,000.0  
Percentage of warrant coverage   5.00%    
Number of warrant instruments | item   4    
Shares issued for warrants | shares   288,184    
Fair value of warrants   $ 900,000    
Warrant exercise period   10 years    
Warrant stand-by period   6 months    
Commitment fee $ 750,000 $ 200,000    
Warrant exercise price (in dollars per share) | $ / shares   $ 3.47    
Amortization of debt discount     2,300,000 $ 700,000
Interest expense     $ 2,100,000  
Horizon Notes [Member] | Minimum        
Debt Instrument [Line Items]        
Debt instrument covenant, required cash balance   $ 8,000,000    
Horizon Notes [Member] | Maximum [Member]        
Debt Instrument [Line Items]        
Debt instrument covenant, required cash balance   $ 13,000,000    
Horizon Notes [Member] | LIBOR Rate [Member]        
Debt Instrument [Line Items]        
Variable interest rate floor (as a percent)   2.50%