Quarterly report pursuant to Section 13 or 15(d)

Equity Awards - Activity (Details)

v3.22.2.2
Equity Awards - Activity (Details)
$ in Thousands
 3 Months Ended 12 Months Ended
Aug. 31, 2022
USD ($)
Y
$ / shares
shares
May 31, 2022
USD ($)
$ / shares
shares
Jun. 24, 2022
$ / shares
Y
May 31, 2021
USD ($)
Liability Classified Warrants        
Derivative liability (beginning balance) | $      
Classified as liability due to lack of shares availability at issuance | $ 14,522      
Classified as equity upon increase in availability | $ (23,123)      
Loss on derivative due to change in fair market value | $ 8,601      
Derivative liability (ending balance) | $    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Carrying value of Note | $ $ 43,953     $ 42,215
Stock option and warrant activity        
Options and warrants outstanding, Number of Shares | shares 90,705      
Granted, Number of Shares | shares 104,104      
Exercised, Number of Shares | shares (863)      
Forfeited/expired/cancelled, Number of Shares | shares (484)      
Options and warrants outstanding, Number of Shares | shares 193,462 90,705    
Options and warrants outstanding and exercisable, Number of Shares | shares 187,896      
Options and warrants outstanding, Weighted Average Exercise Price | $ / shares $ 0.77      
Granted, Weighted Average Exercise Price | $ / shares 0.25      
Exercised, Weighted Average Exercise Price | $ / shares 0.49      
Forfeited/expired/cancelled, Weighted Average Exercise Price | $ / shares 1.57      
Options and warrants outstanding, Weighted Average Exercise Price | $ / shares 0.48 $ 0.77    
Options and warrants outstanding and exercisable, Weighted Average Exercise Price | $ / shares $ 0.45      
Options and warrants outstanding, Weighted Average Remaining Contractual Life in Years 4 years 4 months 9 days 4 years 21 days    
Options and warrants outstanding and exercisable, Weighted Average Remaining Contractual Life in Years 4 years 2 months 26 days      
Options and warrants outstanding, Aggregate Intrinsic Value | $ $ 36,758 $ 352    
Options and warrants outstanding and exercisable, Aggregate Intrinsic Value | $ $ 36,717      
Stock option vested, Shares | shares 11,900,000      
Options outstanding, nonvested | shares 5,300,000      
Loss on derivatives | $ $ 8,601      
Fair value of underlying stock | Level 3 Inputs | Placement Agent Warrants        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability | $ / shares 0.52   0.44  
Fair value of underlying stock | Level 3 Inputs | Back Stop Warrant #1        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability | $ / shares 0.52   0.44  
Fair value of underlying stock | Level 3 Inputs | Back Stop Warrant #2        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability | $ / shares 0.52   0.42  
Risk free rate | Level 3 Inputs | Placement Agent Warrants        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability 0.0316   0.0313  
Risk free rate | Level 3 Inputs | Back Stop Warrant #1        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability 0.0334   0.0317  
Risk free rate | Level 3 Inputs | Back Stop Warrant #2        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability 0.0331   0.0306  
Expected term (in years) | Level 3 Inputs | Placement Agent Warrants        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability | Y 9.82   10.00  
Expected term (in years) | Level 3 Inputs | Back Stop Warrant #1        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability | Y 4.46   4.65  
Expected term (in years) | Level 3 Inputs | Back Stop Warrant #2        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability | Y 4.88   5.00  
Stock price volatility | Level 3 Inputs | Placement Agent Warrants        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability 0.9587   0.9599  
Stock price volatility | Level 3 Inputs | Back Stop Warrant #1        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability 1.1729   1.1020  
Stock price volatility | Level 3 Inputs | Back Stop Warrant #2        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability 1.1359   1.0949  
Expected dividend yield | Level 3 Inputs | Placement Agent Warrants        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability 0.0000   0.0000  
Expected dividend yield | Level 3 Inputs | Back Stop Warrant #1        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability 0.0000   0.0000  
Expected dividend yield | Level 3 Inputs | Back Stop Warrant #2        
Fair Value Measurement Inputs and Valuation Techniques [Line Items]        
Derivative liability 0.0000   0.0000