Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt, Net of Financing Fees - Narrative (Details)

v3.21.2
Long-Term Debt, Net of Financing Fees - Narrative (Details)
$ / shares in Units, $ in Thousands
3 Months Ended 9 Months Ended
Dec. 10, 2020
USD ($)
$ / shares
shares
Jun. 30, 2020
USD ($)
fiscal_quarter
Sep. 30, 2021
USD ($)
Sep. 30, 2020
USD ($)
Sep. 30, 2021
USD ($)
Sep. 30, 2020
USD ($)
Jun. 30, 2021
USD ($)
Mar. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Debt Instrument [Line Items]                  
Financing costs paid         $ 0 $ 642      
Interest expense     $ 417 $ 397 1,427 $ 459      
Restricted cash     6,333   6,333       $ 6,842
Standby Letters of Credit | Heights Union                  
Debt Instrument [Line Items]                  
Collateral amount     250   250     $ 250  
Restricted Cash                  
Debt Instrument [Line Items]                  
Collateral amount     $ 6,000   6,000       6,000
Oberland Option                  
Debt Instrument [Line Items]                  
Exercise price of warrants (in USD per share) | $ / shares $ 14.13                
Oberland Option | TPC Investments II LP, A Wholly Owned Subsidiary Of Oberland Capital                  
Debt Instrument [Line Items]                  
Shares called by warrants (in shares) | shares 247,699                
Oberland Facility                  
Debt Instrument [Line Items]                  
Term of debt   7 years              
Financing costs   $ 642              
Financing costs paid         $ 642        
Period for which quarterly interest payments should be made   7 years              
Interest rate   7.50%              
Interest rate at period end     9.50%   9.50%        
Threshold revenue achievement for payment of additional quarterly royalty   $ 70,000              
Additional payment percentage   1.00%              
Interest expense     $ 337   $ 590        
Cash paid for interest     1,218   2,890        
Interest capitalized     1,338   2,526        
Accumulated capitalized interest costs     3,495   $ 3,495        
Make-whole payment, minimum required internal rate of return   11.50%              
Increase in interest rate   4.00%              
Liquidity covenant multiplier   1.1              
Oberland Facility | Each of Third And Fourth Quarter of 2020                  
Debt Instrument [Line Items]                  
Revenue target   $ 8,750              
Oberland Facility | Each Of The First And Second Quarter of 2021                  
Debt Instrument [Line Items]                  
Revenue target   17,500              
Oberland Facility | Each Quarter After The Second Quarter of 2021                  
Debt Instrument [Line Items]                  
Revenue target   20,000              
Oberland Facility | Oberland Option                  
Debt Instrument [Line Items]                  
Value of warrants outstanding   $ 3,500              
Moving average of closing stock         45 days        
Gross proceeds from warrant exercises $ 3,500                
Oberland Facility | LIBOR                  
Debt Instrument [Line Items]                  
Additional interest floor rate   2.00%              
First Tranche                  
Debt Instrument [Line Items]                  
Oberland Facility   $ 35,000 35,000   $ 35,000       35,000
First Tranche | Debt derivative liabilities                  
Debt Instrument [Line Items]                  
Fair value of derivatives   2,387              
Second Tranche                  
Debt Instrument [Line Items]                  
Oberland Facility     $ 15,000   $ 15,000   $ 15,000   $ 0
Second Tranche | Debt derivative liabilities                  
Debt Instrument [Line Items]                  
Fair value of derivatives   1,173              
Third Tranche                  
Debt Instrument [Line Items]                  
Contingent additional borrowing capacity   $ 25,000              
Number of quarters | fiscal_quarter   2              
Revenue threshold necessary to obtain additional borrowing   $ 28,000