Long-Term Debt - Schedule of Debt (Details) - USD ($)	May 31, 2016	May 31, 2015
Total Notes Payable	$ 15,446,748	$ 12,579,011
Less: Current portion	(2,088,327)	(2,278,164)
Long-term Debt	13,358,421	10,300,847
Term Note A Payable To International Bank of Commerce, Prime Rate of Interest Plus 0.5% But Not Less Than 4%, Maturing January 7, 2019 [Member]
Total Notes Payable	5,310,179
Term Note B Payable To International Bank of Commerce, Prime Rate of Interest Plus 0.5% But Not Less Than 4%, Maturing January 7, 2019 [Member]
Total Notes Payable	2,688,659
Term Note Payable To International Bank of Commerce, Interest Rate of 4.5%, Refinanced January 7, 2016 [Member]
Total Notes Payable		6,945,884
Revolving Note Ppayable to International Bank of Commerce, Prime Rate of Interest Plus 0.5% But Not Less Than 4.0%, Due January 31, 2018 [Member]
Total Notes Payable	1,675,000	300,000
Term Note Payable by GRE to International Bank of Commerce, Interest Rate of 4.5%, Monthly Principal and Interest Payments of $26,215, Due January 31, 2019 [Member]
Total Notes Payable	3,021,734	3,207,553
Note Payable to Robert Rosene, 7.5% Interest, Due January 15, 2018 [Member]
Total Notes Payable	2,066,000	2,066,000
Note Payable to Yorktown Management & Financial Services, LLC, 5.0% Interest, Due February 28, 2019, Monthly Principal and Interest Payments of $20,629 [Member]
Total Notes Payable	634,616
Other Note Payable [Member]
Total Notes Payable	$ 50,560	$ 59,574