Convertible Instruments and Accrued Interest - Components (Details) $ in Thousands  | 
3 Months Ended | 
|---|---|
| 
 Aug. 31, 2022  
USD ($) 
 | |
| Debt Instrument [Line Items] | |
| Outstanding balance, beginning | $ 42,215 | 
| Amortization of issuance discount and costs | 592 | 
| Interest expense | 1,146 | 
| Outstanding balance, ending | 43,953 | 
| Long-term Convertible Note - April 2, 2021 Note | |
| Debt Instrument [Line Items] | |
| Outstanding balance, beginning | 11,906 | 
| Amortization of issuance discount and costs | 153 | 
| Interest expense | 321 | 
| Outstanding balance, ending | 12,380 | 
| Long-term Convertible Note - April 23, 2021 Note | |
| Debt Instrument [Line Items] | |
| Outstanding balance, beginning | 30,309 | 
| Amortization of issuance discount and costs | 439 | 
| Interest expense | 825 | 
| Outstanding balance, ending | $ 31,573 | 
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- Definition Represents the portion of interest accrued in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs. No definition available. 
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- Definition Amount of amortization expense attributable to debt discount (premium) and debt issuance costs. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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