XML 23 R29.htm IDEA: XBRL DOCUMENT v2.4.0.6
Related Parties Sponsor, Trustee, Custodian and Marketing Agent Fees - Additional Information (Detail) (USD $)
 12 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2010
Related Parties - Sponsor, Trustee, Custodian and Marketing Agent Fees (Textual) [Abstract]      
Trustee minimum fee $ 500,000    
Trustee maximum fee 2,000,000    
Sponsor [Member]
      
Related Parties - Sponsor, Trustee, Custodian and Marketing Agent Fees (Textual) [Abstract]      
Related party fees payable at annual rate 0.15%    
Trustee [Member]
      
Related Parties - Sponsor, Trustee, Custodian and Marketing Agent Fees (Textual) [Abstract]      
Related party fees payable at annual rate 0.02%    
Custodian Tier One [Member]
      
Related Parties - Sponsor, Trustee, Custodian and Marketing Agent Fees (Textual) [Abstract]      
Related party fees payable at annual rate 0.10%    
Aggregate weight of gold to determine custodian fee tiers 4,500,000    
Custodian Tier Two [Member]
      
Related Parties - Sponsor, Trustee, Custodian and Marketing Agent Fees (Textual) [Abstract]      
Related party fees payable at annual rate 0.06%    
Aggregate weight of gold to determine custodian fee tiers 4,500,000    
Marketing Agent [Member]
      
Related Parties - Sponsor, Trustee, Custodian and Marketing Agent Fees (Textual) [Abstract]      
Related party fees payable at annual rate 0.15%    
Sponsor And Marketing Agent [Member]
      
Related Parties - Sponsor, Trustee, Custodian and Marketing Agent Fees (Textual) [Abstract]      
Trust expense ratio 0.40%    
Assets under management required for Trust accrual 1,200,000,000    
Accounting rate of ordinary expenses after taking affect of current expenses 0.40%    
Sponsor and Marketing Agent combined fees at a rate 0.30%    
Minimum ANAV to Unforeseen Expenses 0.70%    
Ordinary expenses accrual rate if gross assets drop discussion If at the end of any month, the estimated ordinary expenses of the Trust exceed an amount equal to 0.40% per year of the daily ANAV of the Trust for such month, the Sponsor and the Marketing Agent will waive the amount of such excess from the fees payable to them from the assets of the Trust for such month in equal shares up to the amount of their fees.    
Unforeseen expenses of the Trust discussion If the Trust incurs unforeseen expenses that cause the total ordinary expenses of the Trust to exceed 0.70% per year of the daily ANAV of the Trust, the ordinary expenses will accrue at a rate greater than 0.40% per year of the daily ANAV of the Trust, even after the Sponsor and the Marketing Agent have completely waived their combined fees    
Sponsor and Marketing Agent fees reduction $ 0 $ 6,865 $ 175,823