Warrants Outstanding (Details) (USD $)	12 Months Ended
	May 31, 2013	May 31, 2011	May 31, 2010	May 31, 2009	May 31, 2008
Warrants Outstanding
Number of common stock purchase warrants outstanding					10,000
Exercise price of Warrants		$ 2.5			$ 40
Number of units sold to an investor for cash		50,000	20,252	10,000
Price per unit sold			$ 2	$ 25
value of units sold		$ 100,000	$ 1,250,000	$ 250,000
Amount assigned to the common stock as the warrants are non-detachable.				$ 250,000
Year-end balance of warrants	50,000	80,252	40,252	20,000
warrants expired during the period	20,252	10,000
Common stock exercise prices minimum range			$ 20
Common stock exercise prices maximum range			$ 125
Minimum range per unit sold to investors for cash			$ 17
Maximum range per unit sold to investors for cash			$ 100