Quarterly report pursuant to Section 13 or 15(d)

Public Warrant Tender Offerings - Additional Information (Detail)

v3.20.1
Public Warrant Tender Offerings - Additional Information (Detail) - USD ($)
 2 Months Ended
Dec. 06, 2019
Jul. 31, 2019
Feb. 29, 2020
May 31, 2019
Public Warrant Tender Offerings [Line Items]        
Common stock, par value     $ 0.001 $ 0.001
Proceeds from issuance of common shares $ 30.023      
Public Warrant Tender Offerings [Member]        
Public Warrant Tender Offerings [Line Items]        
Common stock sold at private equity offering   45,375,923    
Common stock, par value   $ 0.001    
Proceeds from issuance of common shares   $ 11,900,000    
Placement agent fees and expenses   1,100,000    
Noncash inducement interest expense   $ 2,400,000    
Public Warrant Tender Offerings [Member] | Minimum [Member]        
Public Warrant Tender Offerings [Line Items]        
Purchase price, per share   $ 0.30    
Public Warrant Tender Offerings [Member] | Maximum [Member]        
Public Warrant Tender Offerings [Line Items]        
Purchase price, per share   $ 0.40