Annual report pursuant to Section 13 and 15(d)

Borrowings - Additional Information (Details)

v3.21.1
Borrowings - Additional Information (Details)
1 Months Ended 12 Months Ended
Mar. 07, 2019
USD ($)
d
$ / shares
Sep. 30, 2016
USD ($)
Jan. 31, 2021
USD ($)
shares
Dec. 31, 2020
USD ($)
shares
Jun. 30, 2020
USD ($)
shares
Apr. 09, 2020
USD ($)
d
$ / shares
Apr. 30, 2019
USD ($)
shares
Dec. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
Debt Instrument [Line Items]                  
Payment of debt issuance costs               $ 494,000 $ 1,253,000
Amortization of debt issuance costs and discount               1,201,000 1,171,000
Loss on extinguishment of debt               1,766,000 1,045,000
Net carrying amount of convertible debt and derivative liability       $ 16,516,000       $ 16,516,000 11,522,000
April 2020 Note Purchase Agreement                  
Debt Instrument [Line Items]                  
Date of issuance and sale of notes           Apr. 09, 2020      
Face amount           $ 10,000,000.0      
Proceeds from debt, net of issuance costs           9,500,000      
Payment of debt issuance costs           $ 500,000      
Purchase price as percentage of principal amount           100.00%      
Interest rate           6.00%      
Payment terms               The April 2020 Notes will bear interest at a rate of 6.0% per annum, payable semiannually in arrears on April 15 and October 15 of each year, beginning October 15, 2020. The April 2020 Notes will mature on April 15, 2026, unless earlier converted, redeemed or repurchased.    
Notes maturity date           Apr. 15, 2026      
Notes maturity description               The April 2020 Notes will mature on April 15, 2026, unless earlier converted, redeemed or repurchased  
Senior convertible notes       1,200,000       $ 1,200,000  
Unamortized debt issuance cost       100,000       100,000  
Bifurcated embedded conversion option derivative liability       3,300,000       3,300,000  
Derivative, fair value       8,100,000       8,100,000  
Debt issuance costs       400,000       400,000  
Gain (loss) on fair value adjustment of derivative liability               1,700,000  
Amortization of debt issuance costs and discount               200,000  
Conversion of convertible note, amount       $ 2,000,000.0 $ 2,000,000.0        
Conversion of convertible note exchanged for shares | shares       322,348 316,461        
Loss on extinguishment of debt       $ 1,000,000.0 $ 800,000        
Net carrying amount of convertible debt and derivative liability       1,400,000 2,000,000.0     1,400,000  
Fair value of the consideration issued       2,400,000 $ 2,800,000     2,400,000  
Fair value of convertible debt and derivative liability       7,400,000       $ 7,400,000  
Conversion terms               holders of the April 2020 Notes may convert their April 2020 Notes at their option at any time prior to the close of business on the business day immediately preceding April 15, 2026 into shares of the Company’s common stock.  
Conversion rate, number of shares to be issued per $1000 of principal (in shares)           111.1108      
Principal amount of notes used as the denominator for conversion into notes           $ 1,000      
Initial conversion price of notes | $ / shares           $ 9.00      
Conversion rate, number of shares to be issued per $1000 of principal (in shares) after adjustment to certain events           1,938,600      
Convertible notes, redemption start date           Apr. 15, 2023      
Convertible notes, threshold percentage of stock price trigger           130.00%      
Convertible notes, threshold trading days | d           20      
Convertible notes, threshold consecutive trading days | d           30      
Redemption price as percentage of the principal amount           100.00%      
Redemption price as percentage of the principal amount subject to certain exceptions           100.00%      
April 2020 Note Purchase Agreement | Subsequent Event                  
Debt Instrument [Line Items]                  
Conversion of convertible note, amount     $ 6,000,000.0            
Conversion of convertible note exchanged for shares | shares     959,080            
Senior Convertible Note Purchase Agreement                  
Debt Instrument [Line Items]                  
Date of issuance and sale of notes Mar. 07, 2019                
Face amount $ 16,000,000.0                
Proceeds from debt, net of issuance costs 14,700,000                
Payment of debt issuance costs $ 1,300,000                
Purchase price as percentage of principal amount 100.00%                
Interest rate 6.00%                
Payment terms               The March 2019 Notes bear interest at a rate of 6.0% per annum payable semiannually in arrears on March 15 and September 15 of each year, beginning September 15, 2019. The March 2019 Notes will mature on March 15, 2025, unless earlier converted, redeemed or repurchased.   
Notes maturity date Mar. 15, 2025                
Notes maturity description               The March 2019 Notes will mature on March 15, 2025, unless earlier converted, redeemed or repurchased  
Senior convertible notes       9,400,000       $ 9,400,000 8,300,000
Unamortized debt issuance cost       400,000       400,000 500,000
Bifurcated embedded conversion option derivative liability       2,700,000       2,700,000 3,200,000
Derivative, fair value       7,000,000.0       7,000,000.0  
Debt issuance costs       600,000       600,000  
Gain (loss) on fair value adjustment of derivative liability               500,000 1,600,000
Amortization of debt issuance costs and discount               1,000,000.0 1,100,000
Conversion of convertible note, amount             $ 2,000,000.0    
Conversion of convertible note exchanged for shares | shares             162,600    
Loss on extinguishment of debt             $ 200,000   800,000
Net carrying amount of convertible debt and derivative liability             2,800,000    
Fair value of the consideration issued             $ 3,000,000.0    
Fair value of convertible debt and derivative liability       $ 12,900,000       $ 12,900,000 11,700,000
Conversion terms               holder of the March 2019 Notes may convert their March 2019 Notes at their option at any time prior to the close of business on the business day immediately preceding March 15, 2025 into shares of the Company’s common stock.  
Conversion rate, number of shares to be issued per $1000 of principal (in shares) 73.9096                
Principal amount of notes used as the denominator for conversion into notes $ 1,000                
Initial conversion price of notes | $ / shares $ 13.53                
Conversion rate, number of shares to be issued per $1000 of principal (in shares) after adjustment to certain events 81                
Convertible notes, redemption start date Mar. 15, 2022                
Convertible notes, threshold percentage of stock price trigger 130.00%                
Convertible notes, threshold trading days | d 20                
Convertible notes, threshold consecutive trading days | d 30                
Redemption price as percentage of the principal amount 100.00%                
Redemption price as percentage of the principal amount subject to certain exceptions 100.00%                
Reacquisition price of outstanding debt                 15,900,000
Carrying value of debt obligation                 $ 15,100,000
Principal amount of notes used as the denominator for conversion into notes after adjustment of certain events $ 1,000                
Term Loan | Secured Debt                  
Debt Instrument [Line Items]                  
Face amount   $ 15,000,000.0              
Loan agreement term   48 months              
Term Loan | Secured Debt | LIBOR                  
Debt Instrument [Line Items]                  
Basis spread on variable rate (as a percent)   8.49%