Annual report pursuant to Section 13 and 15(d)

Warrants - Additional Information (Details)

v3.20.1
Warrants - Additional Information (Details) - USD ($)
$ in Thousands
 12 Months Ended
May 10, 2019
Nov. 02, 2018
Aug. 30, 2018
Dec. 31, 2019
Dec. 31, 2018
Aug. 31, 2016
Class Of Warrant Or Right [Line Items]            
Number of warrants issued       956 156,294  
Remeasurement of warrant fair value       $ 0 $ 970  
Number of warrants exercised 155,338       5,977  
Cash proceeds from warrants exercised $ 23     $ 23 $ 47  
Reclassification of outstanding warrant liability to equity upon conversion and elimination of preferred stock   $ 1,804        
Series A Preferred Stock            
Class Of Warrant Or Right [Line Items]            
Number of warrants exercised     310,676      
Cash proceeds from warrants exercised     $ 47      
Reclassification of warrant liability to equity upon exercise     $ 2,951      
Series A Preferred Stock | August 2016 PSA Warrant Exercisable in August 2017            
Class Of Warrant Or Right [Line Items]            
Number of warrants issued           155,338
Series A Preferred Stock | August 2016 PSA Warrant Exercisable in August 2018            
Class Of Warrant Or Right [Line Items]            
Number of warrants issued           155,338
Series A Preferred Stock | August 2016 PSA Warrant Exercisable in August 2019            
Class Of Warrant Or Right [Line Items]            
Number of warrants issued           155,338