Inventories, net (Details) - USD ($) $ in Thousands  | 
May 31, 2022  | 
May 31, 2021  | 
|---|---|---|
| Inventories, net | ||
| Raw materials | $ 16,264 | $ 28,085 | 
| Work-in-progress | 1,665 | 65,394 | 
| Inventories, net | $ 17,929 | $ 93,479 | 
| X | ||||||||||
- Definition Amount before valuation and LIFO reserves of raw materials classified noncurrent. No definition available. 
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| X | ||||||||||
- Definition Amount before valuation and LIFO reserves of merchandise or goods in the production process classified noncurrent. No definition available. 
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| X | ||||||||||
- References No definition available. 
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| X | ||||||||||
- Definition Inventories not expected to be converted to cash, sold or exchanged within the normal operating cycle. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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