Summary of significant accounting policies - Narrative (Details) |
3 Months Ended | 9 Months Ended | ||
---|---|---|---|---|
Sep. 30, 2020
USD ($)
$ / shares
|
Sep. 30, 2019
USD ($)
|
Sep. 30, 2020
USD ($)
segment
$ / shares
|
Sep. 30, 2019
USD ($)
|
|
Research and Development Expense [Abstract] | ||||
Reverse stock split ratio | 6 | |||
Change in fair value of warrant liability | $ 5,549,000 | $ 5,549,000 | ||
Research And Development Milestone Expense | $ 0 | $ 0 | $ 0 | $ 0 |
Number of Operating Segments | segment | 1 | |||
IPO share price per share | $ / shares | $ 12.00 | $ 12.00 |