v3.26.3
Convertible Instruments and Accrued Interest - Preferred stock (Details)
$ / shares in Units, shares in Thousands, $ in Thousands
 3 Months Ended 12 Months Ended
Aug. 31, 2026
USD ($)
$ / shares
shares
May 31, 2026
USD ($)
shares
Class of Stock    
Accrued dividends | $ $ 10,016 $ 9,647
Series B Convertible Preferred Stock    
Class of Stock    
Shares of preferred stock outstanding 19 19
Common stock conversion rate 10 10
Total shares of common stock if converted 190 190
Undeclared dividends | $ $ 30 $ 29
Total shares of common stock if dividends converted 60 58
Preferred stock, liquidation preference per share ($ per share) | $ / shares $ 5  
Series C Convertible Preferred Stock    
Class of Stock    
Shares of preferred stock outstanding 6 6
Common stock conversion rate 2,000 2,000
Total shares of common stock if converted 12,390 12,390
Accrued dividends | $ $ 4,458 $ 4,302
Total shares of common stock if dividends converted 8,916 8,604
Series D Convertible Preferred Stock    
Class of Stock    
Shares of preferred stock outstanding 9 9
Common stock conversion rate 1,250 1,250
Total shares of common stock if converted 10,565 10,565
Accrued dividends | $ $ 5,558 $ 5,345
Total shares of common stock if dividends converted 11,116 10,690
Series C and Series D convertible preferred stock [Member]    
Class of Stock    
Preferred stock, liquidation preference per share ($ per share) | $ / shares $ 1,000