Leases (Supplemental Cash Flow Information Related To Leases) (Details) - USD ($)	6 Months Ended
	Oct. 31, 2020	Oct. 31, 2019
Leases [Abstract]
Operating cash flows from finance leases	$ 122,401	$ 142,126
Operating cash flows from operating leases	109,917	126,363
Financing cash flows from finance leases	1,011,945	1,162,403
Right-of-use assets obtained in exchange for new finance lease liabilities		671,446
Right-of-use assets obtained in exchange for operating lease liabilities	$ 1,162,451	$ 1,630,006