| Leases - Schedule of Right-of-Use Assets (Details) - USD ($) | Jul. 31, 2020 | Apr. 30, 2020 | May 01, 2019 | 
|---|---|---|---|
| Leases [Abstract] | 听 | 听 | 听 | 
| Operating office leases | $ 12,356,837 | 听 | 听 | 
| Less accumulated reduction | (5,092,253) | 听 | 听 | 
| Operating lease right of use asset, net | $ 7,264,584 | $ 6,412,851 | $ 8,000,000 | 
| X | ||||||||||
| 
- Definition Operating Lease, Right-of-Use Asset, Accumulated Amortization No definition available. 
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| X | ||||||||||
| 
- Definition Operating Lease, Right-of-Use Asset, before Accumulated Amortization No definition available. 
 | 
| X | ||||||||||
| 
- References No definition available. 
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| X | ||||||||||
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- Definition Amount of lessee's right to use underlying asset under operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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