Derivative Liability - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Nov. 30, 2019	Nov. 30, 2018	Nov. 30, 2019	Nov. 30, 2018
Derivative [Line Items]
Change in fair value of derivative liability	$ 203,166	$ 281,055	$ 828,499	$ (466,412)
Percentage Of Outstanding Common Stock To Be Acquired			50.00%
Warrant [Member]
Derivative [Line Items]
Change in fair value of derivative liability			$ 280,000	$ (466,000)
Convertible Note [Member]
Derivative [Line Items]
Change in fair value of derivative liability			$ 549,000