Loss Per Common Share - Summary of Weighted Average Number of Shares of Common Stock Outstanding (Details) - shares shares in Thousands	9 Months Ended
	Feb. 28, 2023	Feb. 28, 2022
Stock options, warrants & unvested restricted stock
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities excluded from computation of loss per common share	203,274	98,309
Convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities excluded from computation of loss per common share	12,000	12,000
Convertible Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities excluded from computation of loss per common share	33,323	32,197