Consolidated Statements of Income - USD ($)	12 Months Ended
	May. 31, 2015	May. 31, 2014
Income Statement [Abstract]
Sales	$ 22,293,922	$ 23,449,936
Cost of Sales	18,269,192	18,107,627
Gross Profit	4,024,730	5,342,309
General, Selling and Administrative Expenses	2,168,762	2,409,115
Operating Income	1,855,968	2,933,194
Other Income (Expense):
Other income	2,500	5,000
Interest expense	(818,136)	(846,568)
Total Other Expense, net	(815,636)	(841,568)
Income before Income Taxes	1,040,332	2,091,626
(Provision for) Benefit from Income Taxes	(430,763)	1,040,000
Net Income	609,569	3,131,626
Income Attributable to Variable Interest Entity	(227,004)	(200,563)
Preferred Dividends	(325,000)	(325,000)
Net Income Attributable to Common Stockholders	$ 57,565	$ 2,606,063
Income Per Share of Common Stock -
Basic	$ 0.00	$ 0.10
Diluted	$ 0.00	$ 0.09
Weighted Average Shares of Common Stock Outstanding -
Basic	26,975,312	26,198,701
Diluted	27,771,466	27,674,939