Statements of Cash Flows (Unaudited) (USD $)
6 Months Ended
Apr. 30, 2013
Apr. 30, 2012
Cash flows from operating activities    
Cash paid for expenses $ (648,609) $ (920,714)
Net cash used in operating activities (648,609) (920,714)
Cash flows from financing activities    
Cash received to purchase redeemable shares 26,389,742 42,919,644
Cash paid to redeem redeemable shares (68,604,661) (193,212,956)
Net cash used in financing activities (42,214,919) (150,293,312)
Adjustment to period cash flows due to currency movement 694,723 (25,104,568)
Decrease in cash (42,168,805) (176,318,594)
Cash at beginning of period 333,082,495 567,642,010
Cash at end of period 290,913,690 391,323,416
Reconciliation of net loss to net cash used in operating activities    
Net Loss (634,683) (861,329)
Adjustments to reconcile net loss to net cash used in operating activities:    
Prior period receivable from accrued interest (139)  
Currency translation adjustment (182) 8,400
Accrued sponsor fee 100,553 128,758
Prior period accrued sponsor fee $ (114,158) $ (196,543)