Annual report pursuant to Section 13 and 15(d)

Stockholders' deficit, Preferred Stock (Details)

v3.20.1
Stockholders' deficit, Preferred Stock (Details) - USD ($)
$ / shares in Units, $ in Millions
 1 Months Ended
Feb. 12, 2019
Dec. 12, 2018
Dec. 31, 2018
May 06, 2019
Class of Stock [Line Items]        
Unit price (in dollars per share)   $ 1.95    
Shares issued pursuant to a private placement - net proceeds   $ 2.7    
Share issuance costs   $ 0.1    
Series A Preferred Stock [Member]        
Class of Stock [Line Items]        
Shares issued pursuant to a private placement - net proceeds (in shares) 69,115   2,391,403  
Unit price (in dollars per share) $ 2.17   $ 2.17  
Shares issued pursuant to a private placement - net proceeds $ 0.2   $ 4.7  
Share issuance costs     $ 0.5  
Shares issued in stock conversion (in shares)       2,460,517