Annual report pursuant to Section 13 and 15(d)

Registered Direct Equity Offerings - Additional Information (Detail)

v3.20.2
Registered Direct Equity Offerings - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 1 Months Ended 6 Months Ended
Dec. 23, 2019
Dec. 13, 2019
Dec. 09, 2019
Apr. 05, 2019
Jun. 15, 2018
Feb. 13, 2019
Nov. 30, 2019
Jun. 30, 2020
Feb. 04, 2020
May 31, 2018
Stockholders Equity Note [Line Items]                    
Warrants to purchase common shares, shares                 833,332  
Class of warrants, exercise price             $ 0.45      
Term of warrants       5 years            
Definitive Subscription Agreement [Member]                    
Stockholders Equity Note [Line Items]                    
Minority interest amount $ 500                  
Minimum                    
Stockholders Equity Note [Line Items]                    
Purchase price, per share               $ 0.35    
Maximum                    
Stockholders Equity Note [Line Items]                    
Purchase price, per share               $ 1.35    
Placement Agent                    
Stockholders Equity Note [Line Items]                    
Warrants to purchase common shares, shares       938,790 133,600 965,563 655,305      
Class of warrants, exercise price       $ 0.50 $ 0.55 $ 0.50        
Term of warrants         5 years 5 years 5 years     5 years
Percentage of shares, issued as warrants       9.00% 8.00% 9.00% 1.30%      
Placement Agent | Minimum                    
Stockholders Equity Note [Line Items]                    
Class of warrants, exercise price             $ 0.40      
Placement Agent | Maximum                    
Stockholders Equity Note [Line Items]                    
Class of warrants, exercise price             $ 0.444      
Subscription Agreements                    
Stockholders Equity Note [Line Items]                    
Number of shares to be sold 14,754,098 2,433,333 2,568,330 10,931,000 1,970,000 10,728,480 19,100,333      
Purchase price, per share $ 0.305 $ 0.30 $ 0.30 $ 0.50 $ 0.50 $ 0.50        
Warrants to purchase common shares, shares         1,970,000   11,987,250      
Class of warrants, exercise price         $ 0.75   $ 0.45      
Term of warrants         5 years   5 years      
Proceeds from issuance of common shares $ 4,500       $ 900   $ 6,300      
Subscription Agreements | Minimum                    
Stockholders Equity Note [Line Items]                    
Purchase price, per share             $ 0.30      
Subscription Agreements | Maximum                    
Stockholders Equity Note [Line Items]                    
Purchase price, per share             $ 0.40      
2019 Subscription Agreement                    
Stockholders Equity Note [Line Items]                    
Warrants to purchase common shares, shares 7,377,049 1,825,000 1,926,248 5,465,500   5,364,240        
Class of warrants, exercise price   $ 0.45 $ 0.45 $ 0.50   $ 0.50        
Term of warrants   5 years 5 years 5 years   5 years        
Proceeds from issuance of common shares   $ 730 $ 750 $ 5,000   $ 4,800        
Phoenixus AG [Member]                    
Stockholders Equity Note [Line Items]                    
Minority interest amount $ 4,000