Quarterly report pursuant to Section 13 or 15(d)

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Detail)

v3.8.0.1
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Detail) - USD ($)
3 Months Ended
Aug. 31, 2017
Aug. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share based compensation, number of stock options outstanding 4,180,543  
Aggregate unrecognized compensation cost of unvested options $ 0  
Share based compensation, number of stock options expired during period 400,000  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number 3,980,543  
Operating Expense    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Compensation cost included in operating expenses $ 0 $ 180,333
Stock Option    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount 3,980,543 3,982,543