Quarterly report pursuant to Section 13 or 15(d)

Stockholders' deficit - Equity transactions (Details)

v3.21.1
Stockholders' deficit - Equity transactions (Details) - USD ($)
$ / shares in Units, $ in Thousands
Jan. 22, 2021
Mar. 31, 2021
Dec. 31, 2020
Dec. 12, 2018
Class of Stock [Line Items]        
Common stock, par value (in dollars per share)   $ 0.001 $ 0.001  
Number of warrants included in each unit (in shares)       1
Number of shares issuable per warrant (in shares)       0.50
PIPE transaction        
Class of Stock [Line Items]        
Gross consideration $ 4,100      
Purchase price (in dollars per share) $ 1.25      
Number of shares of stock included in each unit (in shares) 1      
Common stock, par value (in dollars per share) $ 0.001      
Number of warrants included in each unit (in shares) 1      
Number of shares issuable per warrant (in shares) 1      
PIPE transaction | Officers and directors        
Class of Stock [Line Items]        
Proceeds from shares and warrants issued pursuant to private placement, net $ 1,600