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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details Textual) | 9 Months Ended
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Sep. 30, 2012
Description Of Creations and Redemptions | Effective February 29, 2012, Authorized Purchasers may purchase Creation Baskets or redeem Redemption Baskets only in blocks of 50,000 units at a price equal to the NAV of the units calculated shortly after the close of the core trading session on the NYSE Arca on the day the order is placed. Prior to February 29, 2012, Authorized Purchasers could only purchase Creation Baskets or redeem Redemption Baskets in blocks of 100,000 units.

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- Definition Disclosure of creations and redemptions of baskets in block of stock units. + References No definition available. + Details
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