3. FAIR VALUE (Details 3) (USD $)	Jul. 31, 2014	Apr. 30, 2014
Current Assets
Cash and cash equivalents	$ 21,957,661	$ 58,320,555
Marketable securities	4,166,081	0
Long-term Assets
Marketable securities	30,320,490	0
Current Liabilities
Warrant liabilities	680,680	954,876
Level 1
Current Assets
Cash and cash equivalents	21,957,661	58,320,555
Current Liabilities
Warrant liabilities	0	0
Level 2
Current Assets
Cash and cash equivalents	0	0
Marketable securities	4,166,081	0
Long-term Assets
Marketable securities	30,320,490	0
Current Liabilities
Warrant liabilities	0	0
Level 3
Current Assets
Cash and cash equivalents	0	0
Current Liabilities
Warrant liabilities	$ 680,680	$ 954,876