CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEICIT (Parenthetical) - USD ($)
$ in Thousands
3 Months Ended
Dec. 31, 2019
Sep. 30, 2018
Prefunded common stock warrants    
Issuance costs and underwriter fees $ 1,797  
Common stock | Follow-on public offering    
Issuance costs and underwriter fees $ 4,017  
Common stock | Initial public offering    
Issuance costs and underwriter fees   $ 9,935