License Agreements - Additional Information (Detail)  | 
 May 31, 2018  
USD ($) 
 | 
 Mar. 15, 2018  
USD ($) 
 | 
 Mar. 15, 2018  
GBP (£) 
 | 
 May 31, 2017  
USD ($) 
 | 
|---|---|---|---|---|
| Licenses Agreements [Line Items] | ||||
| Accrued license fee | $ 133,600 | $ 400,000 | £ 300,000 | $ 167,000 | 
| Royalty on every net sales | 2.00% | 
| X | ||||||||||
- Definition Accrued license fees current. No definition available. 
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| X | ||||||||||
- Definition Licenses Agreements [Line Items] No definition available. 
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| X | ||||||||||
- Definition Potential royalty payment as percentage of net sales. No definition available. 
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