Annual report pursuant to Section 13 and 15(d)

Organization and Description of Business (Narrative) (Details)

v3.21.1
Organization and Description of Business (Narrative) (Details) - USD ($)
Sep. 30, 2020
Dec. 31, 2020
Dec. 31, 2019
Mar. 29, 2019
Accumulated deficit   $ (185,474,000) $ (125,459,000)  
Horizon Notes [Member]        
Debt instrument face value $ 15,000,000.0     $ 20,000,000.0
Debt instrument, prepayment penalties 550,000      
Debt instrument, fee 750,000     $ 200,000
Accrued and unpaid interest $ 112,500