Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($)	May 31, 2018	May 31, 2017
Face value of long-term debt	$ 19,251,596	$ 18,032,416
Less: Debt issue costs, net of amortization	(91,370)	(228,426)
Long-term debt total	19,160,226	17,803,990
Less: Current Portion	(2,324,046)	(2,493,236)
Long-term debt	16,836,180	15,310,754
Term Loan A Payable to International Bank of Commerce, Prime Rate of Interest Plus 0.5% But Not Less Than 4.0%, Maturing April 30, 2023 [Member]
Face value of long-term debt	3,945,443	4,626,191
Term Loan B Payable to International Bank of Commerce, Prime Rate of Interest Plus 0.5% But Not Less Than 4.0%, Maturing January 7, 2019 [Member]
Face value of long-term debt		1,715,132
Term Loan C Payable to International Bank of Commerce, Prime Rate of Interest Plus 0.5% But Not Less Than 4.0%, Maturing August 4, 2020 [Member]
Face value of long-term debt	1,613,445
Term Loan D Payable to International Bank of Commerce, Prime Rate of Interest Plus 0.5% But Not Less Than 4.75%, Maturing January 10, 2022 [Member]
Face value of long-term debt	2,314,935
Term Loan E Payable to International Bank of Commerce, Prime Rate of Interest Plus 0.5% But Not Less Than 4.75%, Maturing January 10, 2022 [Member]
Face value of long-term debt	843,200
Revolving Loan Payable to International Bank of Commerce, Prime Rate of Interest Plus 0.5% But Not Less Than 4.75%, Due January 31, 2020 [Member]
Face value of long-term debt	1,879,000	2,260,000
Term Loan Payable By GRE to International Bank of Commerce, Interest Rate of 4.5%, Monthly Principal And Interest Payments Of $26,215, Due April 30, 2023 [Member]
Face value of long-term debt	2,652,428	2,841,285
Note Payable to Robert Rosene, 7.5% Interest, Due January 15, 2020 [Member]
Face value of long-term debt	4,469,355	4,469,355
Note Payable to First Bank, Prime Rate of Interest Plus 1.45% But Not Less Than 4.95%, Monthly Principal and Interest Payment of $30,628, Due August 21, 2021 [Member]
Face value of long-term debt	1,099,447	1,396,448
Note Payable to Yorktown Management & Financial Services, LLC, 5.0% Interest, Due February 28, 2019, Monthly Principal and Interest Payments of $20,629 [Member]
Face value of long-term debt	181,850	413,969
Other Note Payable [Member]
Face value of long-term debt	$ 252,493	$ 310,036

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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