| Stockholders' Equity - Stock Options (Details) - USD ($) | 12 Months Ended | |
|---|---|---|
| Apr. 30, 2022 | Apr. 30, 2021 | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | Ìý | Ìý | 
| Unrecognized compensation costs | $ 5,446 | Ìý | 
| Stock Incentive Plan and Stock Option Grants to Employees and Directors | Ìý | Ìý | 
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | Ìý | Ìý | 
| Granted (in shares) | 0 | 0 | 
| Stock options | Ìý | Ìý | 
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | Ìý | Ìý | 
| Weighted average recognition period | 5 months 1 day | Ìý | 
| X | ||||||||||
| 
- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
 | 
| X | ||||||||||
| 
- Definition Amount of cost to be recognized for option under share-based payment arrangement. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
 | 
| X | ||||||||||
| 
- 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. 
 | 
| X | ||||||||||
| 
- Definition Gross number of share options (or share units) granted during the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
 | 
| X | ||||||||||
| 
- Details 
 | 
| X | ||||||||||
| 
- Details 
 |