Summary of Business and Significant Accounting Policies (Details Textual)	12 Months Ended
	May 31, 2020 USD ($) Customers	May 31, 2019 USD ($) Customers
Summary of Business and Significant Accounting Policies (Textual)
Number of customers | Customers	3	3
Concentration risk percentage		10.00%
Constituting combined risk percentage	53.30%	51.40%
Largest concentration risk percentage	21.20%	22.50%
Accounts receivable with largest customers | $	$ 3,747,000	$ 3,657,000
Accounts Receivable [Member]
Summary of Business and Significant Accounting Policies (Textual)
Largest concentration risk percentage	53.10%