Annual report pursuant to Section 13 and 15(d)

Warrant derivative liability, Private placement (Details)

v3.20.1
Warrant derivative liability, Private placement (Details) - USD ($)
$ / shares in Units, $ in Millions
 1 Months Ended 12 Months Ended
Jan. 03, 2020
Jan. 08, 2019
Dec. 12, 2018
Dec. 31, 2018
Dec. 31, 2019
Mar. 17, 2020
Nov. 30, 2018
Private Placement Offering [Abstract]              
Units issued in private placement offering (in shares)     1,425,641        
Number of shares issuable per unit (in shares)         1.1    
Unit price (in dollars per share)     $ 1.95        
Gross proceeds from private placement offering     $ 2.8        
Share issuance costs     0.1        
Net proceeds from private placement offering     $ 2.7        
Cash payable if warrants settled in cash         $ 1.1    
Number of warrants issuable if settled (in shares)         1,259,498    
Subsequent Event [Member]              
Private Placement Offering [Abstract]              
Shares issued in private placement offering (in shares) 308,642            
Warrant [Member]              
Private Placement Offering [Abstract]              
Number of shares issuable per unit (in shares)     0.5       0.5
Warrants, exercisable period         2 years    
Warrants, exercise price (in dollars per share)         $ 3.90    
Warrant [Member] | Subsequent Event [Member]              
Private Placement Offering [Abstract]              
Number of shares issuable per unit (in shares)           1,003,232  
Warrants, exercise price (in dollars per share)           $ 1.62  
Common Stock [Member]              
Private Placement Offering [Abstract]              
Number of shares issuable per unit (in shares)     1       1
Net proceeds from private placement offering   $ 0.1   $ 2.6      
Shares issued in private placement offering (in shares)   25,641   1,400,000 0    
Number of warrants issuable if settled (in shares)         712,823