Stockholders' Equity - Schedule of Outstanding Stock Warrants (Details) - Stock Warrants [Member]	6 Months Ended
	Nov. 30, 2020 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Warrants, Outstanding, Beginning balance | shares	803,000
Number of Warrants, Granted | shares	17,054
Number of Warrants, Cancelled | shares
Number of Warrants, Outstanding, Ending balance | shares	820,054
Number of Warrants, Exercisable, Ending balance | shares	820,054
Weighted Average Exercise Price, Outstanding, Beginning balance | $ / shares	$ 83.04
Weighted Average Exercise Price, Granted | $ / shares	21.99
Weighted Average Exercise Price, Cancelled | $ / shares
Weighted Average Exercise Price, Outstanding, Ending balance | $ / shares	81.74
Weighted Average Exercise Price, Exercisable, Ending balance | $ / shares	$ 81.74
Weighted Average Remaining Contractual Term (Years), Outstanding, Ending balance	3 years 1 month 6 days
Weighted Average Remaining Contractual Term (Years), Exercisable, Ending balance	3 years 1 month 6 days
Aggregate Intrinsic Value, Outstanding, Beginning balance | $
Aggregate Intrinsic Value, Outstanding, Ending balance | $
Aggregate Intrinsic Value, Exercisable, Ending balance | $