Quarterly report pursuant to Section 13 or 15(d)

Estimated Fair Value of Warrants is Determined using Black-Scholes Option Valuation Model (Detail)

v3.8.0.1
Estimated Fair Value of Warrants is Determined using Black-Scholes Option Valuation Model (Detail)
9 Months Ended
Feb. 28, 2018
$ / shares
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]  
Expected dividend yield 0.00%
Stock price volatility 61.48%
Expected term 1 month
Risk-free interest rate 0.84%
Grant-date fair value $ 0.25