Revenue - Narrative (Details) - USD ($) |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Jan. 31, 2022 |
Jan. 31, 2021 |
Jan. 31, 2022 |
Jan. 31, 2021 |
Apr. 30, 2021 |
|
| Disaggregation of Revenue [Line Items] | Ìý | Ìý | Ìý | Ìý | Ìý |
| Deferred revenue | $ 6,182,781 | Ìý | $ 6,182,781 | Ìý | $ 6,825,014 |
| Recognition of deferred revenue | Ìý | Ìý | $ 5,424,788 | Ìý | Ìý |
| Revenue Benchmark | Non-US | Customer Concentration Risk | Ìý | Ìý | Ìý | Ìý | Ìý |
| Disaggregation of Revenue [Line Items] | Ìý | Ìý | Ìý | Ìý | Ìý |
| Percentage of revenues from students outside the United States | 1.00% | 1.00% | 1.00% | 1.00% | Ìý |
| X |
- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. Reference 1: http://www.xbrl.org/2003/role/disclosureRef |