Cash and Liquidity (Details) (USD $)
3 Months Ended 6 Months Ended 9 Months Ended 12 Months Ended 54 Months Ended 63 Months Ended
Apr. 30, 2013
Apr. 30, 2012
Jul. 31, 2008
Apr. 30, 2013
Apr. 30, 2012
Jul. 31, 2012
Jul. 31, 2011
Jul. 31, 2010
Jul. 31, 2009
Jul. 31, 2012
Apr. 30, 2013
Cash and Liquidity                      
Losses in all previous reporting periods from inception to date $ 1,728,659 $ 811,574 $ 7,187 $ 5,377,572 $ 771,391 $ 2,364,852 $ 3,758,817 $ 36,158 $ 33,714 $ 6,200,728 $ 11,578,300