Assumptions used in Estimating Fair Value of Convertible Note Redemption Provision Derivative Liability (Detail)		6 Months Ended
	Nov. 15, 2018 $ / shares	Nov. 30, 2018 $ / shares
Fair value of underlying stock
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, price per share	$ 0.57	$ 0.58
Risk free rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded Derivative Liability, Measurement Input	0.0278	0.0278
Expected Term (In Years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, expected term	1 year 7 months 9 days	1 year 7 months 9 days
Stock price volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded Derivative Liability, Measurement Input	0.588	0.588
Expected dividend yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, dividend yield	0.00%	0.00%
Discount factor
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded Derivative Liability, Measurement Input	0.85	0.85