Leases (Details Narrative) - USD ($)	6 Months Ended
Nov. 30, 2020	Nov. 30, 2019
Lessee, Lease, Description [Line Items]
Finance lease cost	$ 1,426,378	$ 1,473,740
Amortization of assets	$ 505,935	416,000
Equipment One [Member]
Lessee, Lease, Description [Line Items]
Operating lease term	52 months
Operating lease discount rate	5.40%
Equipment Two [Member]
Lessee, Lease, Description [Line Items]
Operating lease term	48 months
Operating lease discount rate	5.40%
Office Space [Member]
Lessee, Lease, Description [Line Items]
Payments of monthly rental amount	$ 24,000	$ 24,000
Operating lease term	60 months
Operating lease discount rate	5.00%
Sale and Leaseback Agreement [Member] \| Yorktown Production Equipment [Member]
Lessee, Lease, Description [Line Items]
Value of production equipment purchased	$ 968,168
Lease maturity date	Dec. 27, 2022
Bargain purchase option amount	$ 10,000
Sale and Leaseback Agreement [Member] \| Yorktown Production Equipment [Member] \| Initial Thirty Six Months [Member]
Lessee, Lease, Description [Line Items]
Payments of monthly rental amount	27,915
Sale and Leaseback Agreement [Member] \| Yorktown Production Equipment [Member] \| Following Twelve Months [Member]
Lessee, Lease, Description [Line Items]
Payments of monthly rental amount	7,695
Non- Cancelable Financing Leases [Member] \| Production Equipment [Member]
Lessee, Lease, Description [Line Items]
Production equipment gross carrying amount	8,473,357
Three Lease Agreements with Five Year Terms [Member]
Lessee, Lease, Description [Line Items]
Finance lease cost	$ 6,900,000
Finance lease term	5 years
Lease interest rate	7.40%
Lease payment per invoice rate	$ 3.32
Payments of monthly rental amount	$ 153,000

Lease interest rate.

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- Definition

Lease payment per invoice rate.

+ References

No definition available.

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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

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- Definition

The carrying amount as of the balance sheet date of land not owned but under a contract in which the entity has an option to purchase the land.

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Term of lessee's finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- 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.

+ References

No definition available.

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- Definition

Discount rate used by lessee to determine present value of operating lease payments.

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Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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- Definition

Cash payments to lessor's for use of assets under operating leases.

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- Definition

The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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