Liability Measured At Fair Value on Recurring Basis by Level within Fair Value Hierarchy (Parenthetical) (Detail) - USD ($)		Feb. 28, 2018	May 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities fair value	[1]	$ 3,288,799	$ 3,014,667
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets fair value		0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities fair value		$ 0	$ 0

[1] The Company did not have any assets or liabilities measured at fair value using Level 1 or 2 of the fair value hierarchy as of February 28, 2018 and May 31, 2017.