Summary of Lease Activity (Details) - USD ($)	9 Months Ended
Feb. 28, 2022	Feb. 28, 2021
Leases
Amortization of right-of-use assets	$ 721,923	$ 758,902
Interest on lease liabilities	119,000	218,088
Operating lease expense	53,411	61,411
Short-term lease expense	1,101,133	1,117,628
Total	1,995,467	2,156,029
Operating cash flows	119,000	218,088
Financing cash flows	1,248,371	1,407,081
Operating cash flows	$ 53,411	$ 61,411
Weighted-average remaining lease term (in years) - Financing leases	1 year 6 months	2 years 9 months 18 days
Weighted-average remaining lease term (in years) - Operating leases	1 year 10 months 24 days	2 years 2 months 12 days
Weighted-average discount rate - Financing leases	7.30%	7.40%
Weighted-average discount rate - Operating leases	5.40%	5.20%

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Amount of interest expense on finance lease liability.

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Amount of interest paid on finance lease liability.

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Amount of cash outflow for principal payment on finance lease.

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

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Weighted average discount rate for finance lease calculated at point in time.

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of lease cost recognized by lessee for lease contract.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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