Annual report pursuant to Section 13 and 15(d)

Income Taxes - Reconciliation of Tax Rates (Details)

v3.22.2.2
Income Taxes - Reconciliation of Tax Rates (Details) - USD ($)
$ in Thousands
12 Months Ended
May 31, 2022
May 31, 2021
May 31, 2020
Income Tax Disclosure [Abstract]      
Income tax expense $ 0 $ 0 $ 0
Deferred tax benefit $ 0 $ 0 $ 0
Effective Income Tax Rate Reconciliation, Percent [Abstract]      
Income tax provision at statutory rate: 21.00% 21.00% 21.00%
Derivative loss 0.00% 0.00% (1.60%)
Non-deductible debt issuance costs 0.00% 0.00% (0.10%)
Non-deductible interest on convertible notes (0.50%) (0.60%) (1.20%)
Inducement interest expense (0.70%) (1.50%) (1.30%)
Other 1.10% 0.00% (0.30%)
Credit carry forward generated (released) (0.20%) (0.10%) (0.10%)
Non-deductible loss on induced conversion (3.70%) (2.60%) 0.00%
Non-deductible debt discount amortization (0.30%) (0.60%) (0.30%)
IRC section 162(m) limitation (0.10%) (1.10%) (2.40%)
Stock compensation in excess of ASC 718 0.00% 1.70% 3.20%
Non-deductible expense on induced conversion of debt (0.30%) (1.20%) (3.80%)
Valuation allowance (16.30%) (15.00%) (13.10%)
Effective income tax rate 0.00% 0.00% 0.00%
ASC 842 lease accounting $ 117 $ 0