Quarterly report pursuant to Section 13 or 15(d)

Debt (Details)

v3.21.2
Debt (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Dec. 31, 2020
May 31, 2020
Debt Instrument [Line Items]            
Unamortized issuance costs and debt discounts         $ 185,000  
Interest expense $ 1,317,000 $ 429,000 $ 3,561,000 $ 924,000    
Credit Agreement            
Debt Instrument [Line Items]            
Maximum borrowing capacity 60,000,000.0   60,000,000.0      
Remaining borrowing capacity 40,000,000.0   40,000,000.0     $ 10,000,000.0
Unamortized issuance costs and debt discounts 113,000   113,000      
Interest expense 427,000 $ 429,000 1,200,000 $ 1,000,000.0    
Accrued interest     351,000      
Outstanding balance 19,900,000   19,900,000   $ 19,800,000  
Covenant, cash $ 10,000,000.0   $ 10,000,000.0      
Final payment fee, percentage of principal     2.50%      
Credit Agreement | LIBOR            
Debt Instrument [Line Items]            
Basis spread on variable rate     5.65%      
Floor rate 1.50%   1.50%      
Credit Agreement | as of September 27, 2019            
Debt Instrument [Line Items]            
Maximum borrowing capacity $ 10,000,000.0   $ 10,000,000.0      
Credit Agreement | until December 31, 2020            
Debt Instrument [Line Items]            
Maximum borrowing capacity 10,000,000.0   10,000,000.0      
Credit Agreement | until March 31, 2021            
Debt Instrument [Line Items]            
Maximum borrowing capacity 20,000,000.0   20,000,000.0      
Credit Agreement | until March 31, 2022            
Debt Instrument [Line Items]            
Maximum borrowing capacity $ 20,000,000.0   $ 20,000,000.0      
Credit Agreement | Initial interest-only payment period            
Debt Instrument [Line Items]            
Interest-only payments period     24 months      
Credit Agreement | First conditional interest-only payment period            
Debt Instrument [Line Items]            
Interest-only payments period     36 months      
Credit Agreement | Second conditional interest-only payment period            
Debt Instrument [Line Items]            
Interest-only payments period     48 months      
Credit Agreement | Extended conditional interest-only payment period            
Debt Instrument [Line Items]            
Interest-only payments period     36 months