Quarterly report pursuant to Section 13 or 15(d)

Loan from National Brain Tumor Society and National Foundation for Cancer Research - Additional information (Detail)

v3.20.2
Loan from National Brain Tumor Society and National Foundation for Cancer Research - Additional information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Guarantee Obligations [Line Items]    
Warrants exercised for cash $ 994 $ 26
Warrant [Member]    
Guarantee Obligations [Line Items]    
Warrants exercise price $ 30  
National Brain Tumor Society and National Foundation for Cancer Research [Member]    
Guarantee Obligations [Line Items]    
Loan received $ 500,000  
National Brain Tumor Society [Member] | Warrant [Member]    
Guarantee Obligations [Line Items]    
Warrants issued 125,000  
Warrants exercise price $ 1.09  
Warrants exercised for cash $ 93,701  
Risk-free interest rate 0.37%  
Volatility Rate 89.82%  
Expected Term 5 years  
Dividend Rate 0.00%  
National Brain Tumor Society [Member] | Promissory Note    
Guarantee Obligations [Line Items]    
Accrued interest rate 6.00%  
Debt, maturity date Jun. 19, 2021