| Leases - Schedule of Operating Lease Liabilities (Details) - USD ($) | Jul. 31, 2020 | May 01, 2019 | 
|---|---|---|
| Leases [Abstract] | 听 | 听 | 
| Operating office leases | $ 13,312,573 | 听 | 
| Reduction of lease liabilities | (5,092,253) | 听 | 
| Present value of operating lease obligations | $ 8,220,320 | $ 8,000,000 | 
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- Definition Operating Lease, Liability, Accumulated Reduction No definition available. 
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- Definition Operating Lease, Liability, Gross No definition available. 
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- References No definition available. 
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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