Warrants to purchase common stock outstanding - Stockholders' (Deficiency)/Equity (Details) (USD $)				12 Months Ended			12 Months Ended
	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2013 Warrant Expiration Date 15 December 2014	Jul. 31, 2013 Warrant Expiration Date 4 February 2015	Jul. 31, 2013 Warrant Expiration Date 12 December 2017	Jul. 31, 2013 Warrant Expiration Date 9 February 2015	Jul. 31, 2013 Warrant Expiration Date 7 March 2015	Jul. 31, 2013 Warrant Expiration Date 15 March 2015	Jul. 31, 2013 Warrant Expiration Date 31 March 2016	Jul. 31, 2013 Warrant Expiration Date 11 July 2016	Jul. 31, 2013 Warrant Expiration Date 30 September 2016	Jul. 31, 2013 Warrant Expiration Date 1 February 2017	Jul. 31, 2013 Warrant Expiration Date 10 August 2017	Jul. 31, 2013 Warrant Expiration Date 12 December 2017	Jul. 31, 2013 Warrant Expiration Date 17 June 2018
Number of Shares To be Purchased	220,687,537	55,148,530	80,234,017	8,470,661		24,166,666	300,000	200,000	5,157,813	102,016,744	2,508,560	27,272,720	7,500,000	16,389,512	24,166,666	40,833,335
Warrant Exercise Price per Share				$ 0.76	$ 0.79		$ 0.39	$ 1.25	$ 1.00	$ 0.03	$ 0.03	$ 0.03	$ 0.03	$ 0.03	$ 0.03	$ 0.03
Warrant Expiration Date				Dec. 15, 2014	Feb. 04, 2015		Feb. 09, 2015	Mar. 07, 2015	Mar. 15, 2015	Mar. 31, 2016	Jul. 11, 2016	Sep. 30, 2016	Feb. 01, 2017	Aug. 10, 2017	Dec. 12, 2017	Jun. 17, 2018