Annual report pursuant to Section 13 and 15(d)

Activity Related to Notes (Detail 1)

v3.19.2
Activity Related to Notes (Detail 1) - USD ($)
 12 Months Ended
May 31, 2019
May 31, 2018
May 31, 2017
Debt Instrument [Line Items]      
Monthly redemption provision $ 0    
Note amendment, net 111,410    
Redemptions 0 $ (259,157) $ 0
January 2019 Note 4,654,568    
Interest accretion 298,158    
Short-term Debt [Member]      
Debt Instrument [Line Items]      
Monthly redemption provision 2,100,000    
Note amendment, net 0    
Redemptions 0    
January 2019 Note 4,200,000    
Interest accretion 0    
Long-term Debt [Member]      
Debt Instrument [Line Items]      
Monthly redemption provision (2,100,000)    
Note amendment, net 111,410    
Redemptions (1,455,000)    
January 2019 Note 454,568    
Interest accretion 298,158    
Two Thousand And Eighteen Convertible Notes Member [Member]      
Debt Instrument [Line Items]      
June 2018 Note 5,700,000    
January 2019 Note   5,700,000  
Two Thousand And Eighteen Convertible Notes Member [Member] | Short-term Debt [Member]      
Debt Instrument [Line Items]      
June 2018 Note 2,100,000    
January 2019 Note   2,100,000  
Two Thousand And Eighteen Convertible Notes Member [Member] | Long-term Debt [Member]      
Debt Instrument [Line Items]      
June 2018 Note $ 3,600,000    
January 2019 Note   $ 3,600,000