Geographic Information (Details) - Financial information about foreign and domestic operations and export sales - USD ($)	3 Months Ended
	Aug. 31, 2015	Aug. 31, 2014
Revenues from sales to unaffiliated customers:
Net sales	$ 1,286,993	$ 1,034,450
UNITED STATES
Revenues from sales to unaffiliated customers:
Net sales	187,000	253,000
Asia [Member]
Revenues from sales to unaffiliated customers:
Net sales	433,000	16,000
Europe [Member]
Revenues from sales to unaffiliated customers:
Net sales	619,000	752,000
South America [Member]
Revenues from sales to unaffiliated customers:
Net sales	17,000	3,000
Middle East [Member]
Revenues from sales to unaffiliated customers:
Net sales	$ 31,000	2,000
Other Foreign [Member]
Revenues from sales to unaffiliated customers:
Net sales		$ 9,000