Organization and business (Detail) (USD $)	6 Months Ended	9 Months Ended
	Apr. 24, 2012 Century Concession in Laos [Member] Century Thrust Joint Venture Agreement [Member]	Jul. 31, 2013 Century Concession in Laos [Member] Century Thrust Joint Venture Agreement [Member]	Dec. 31, 2010 Century Concession in Laos [Member] Century Thrust Joint Venture Agreement [Member]	Jul. 31, 2013 Golden Target Pty Ltd, Principal Stockholder [Member]	Jul. 31, 2009 Golden Target Pty Ltd, Principal Stockholder [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Percentage of entity owned				96.21%
Percentage of the entity acquired from certain stockholders					96.00%
Aggregate percentage owned by unrelated entity			70.00%
Potential percentage of investee earnings attributable to Aurum if specified funding is provided by Aurum		72.86%
Potential ownership percentage if funding is provided by Aurum		51.00%
Exploration expense funding commitment, maximum amount		$ 6,500,000
Specified period to meet funding requirements		5 years
Expiration date of specified period to meet funding requirements		Dec. 10, 2015
Mining project option agreement date		Feb. 10, 2011
Additional ownership interest if Aurum had exercised an option to acquire shares held by an unrelated investor before the option expired	20.00%
Potential aggregate ownership interest if Aurum both provides specified funding amounts and exercises an option to acquire shares held by an unrelated investor		71.00%
Monthly required payment to preserve option rights	$ 55,000