Quarterly report pursuant to Section 13 or 15(d)

Warrant derivative liability - Fair value of warrant derivative liability (Details)

v3.20.2
Warrant derivative liability - Fair value of warrant derivative liability (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Sep. 30, 2020
Sep. 30, 2019
Warrant Liability [Roll Forward]          
Balance, beginning of period $ 4,315 $ 841 $ 2,220 $ 2,220  
Change in fair value of derivative liability (4,213) 3,474 (1,379) (2,118) $ (886)
Balance, end of period $ 102 $ 4,315 $ 841 $ 102