Derivative Liability - Additional Information (Detail) - USD ($)	3 Months Ended
	Aug. 31, 2020	Aug. 31, 2019
Derivative [Line Items]
Change in fair value of derivative liability		$ 625,000
Percentage Of Outstanding Common Stock To Be Acquired	50.00%
Warrant [Member]
Derivative [Line Items]
Change in fair value of derivative liability	$ 100,000
Convertible Note [Member]
Derivative [Line Items]
Change in fair value of derivative liability	$ 0	$ 600,000