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ORGANIZATION AND BUSINESS (Additional Information) (Details) (USD $) | 1 Months Ended |  |  |  |  |  |  |  |
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Nov. 30, 2009 | Nov. 18, 2009 | Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2012 | Dec. 31, 2011 | Feb. 29, 2012 Creation Baskets [Member] | Sep. 30, 2013 Open Futures Contracts, Long [Member] United States [Member] Contract | Jul. 01, 2011 Partnership Unit [Member] | Feb. 29, 2012 Prior to February 29, 2012 [Member] Creation Baskets [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of Contracts |  |  |  |  |  |  |  | 713 | [1] |  |
Number of units per basket |  |  |  |  |  |  | 50,000 |  |  |  | 100,000
Fee paid by Authorized Purchasers for each order placed to create one or more Creation Baskets or to redeem one or more baskets |  |  | 350 |  |  |  |  |  |  | 1,000 |
Number of initially registered units on Form S-1 with the U.S. Securities and Exchange Commission | 30,000,000 |  |  |  |  |  |  |  |  |  |
Net asset value per unit |  | $ 50.00 | $ 16.91 | $ 17.23 | $ 18.68 | $ 21.21 |  |  |  |  |
Number of units issued |  | 200,000 |  |  |  |  |  |  |  |  |
Value of unit issued |  | $ 10,000,000 |  |  |  |  |  |  |  |  |
Commenced investment operations date |  | Nov. 18, 2009 |  |  |  |  |  |  |  |  |
Number of registered units |  |  | 30,000,000 |  |  |  |  |  |  |  |
[1] | Collateral amounted to $3,423,834 on open futures contracts.

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