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OFFSETTING ASSETS AND LIABILITIES (Tables) | 3 Months Ended
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Mar. 31, 2013
Offsetting Assets and Liabilities [Line Items] |
Offsetting Assets | Offsetting of Financial Assets and Derivative Assets as of March 31, 2013 and December 31, 2012
Assets |  | Gross Amounts of Recognized Assets |  |  | Gross Amounts Offset in the Statements of Financial Condition |  |  | Net Amounts of Assets Presented in the Statements of Financial Condition |
At March 31, 2013: |  |  |  |  |  |  |  |  |  |  |  |
Futures contracts |  | $ | 77,060 |  |  | $ | — |  |  | $ | 77,060 |
At December 31, 2012: |  |  |  |  |  |  |  |  |  |  |  |
Futures contracts |  | $ | 739,330 |  |  | $ | — |  |  | $ | 739,330 |
Collateral Held By Counterparty [Member] |
Offsetting Assets and Liabilities [Line Items] |
Offsetting Assets | Financial Assets, Derivative Assets, and Collateral Held by Counterparty as of March 31, 2013 and December 31, 2012
|  |  |  |  | Gross Amounts Not Offset in the Statements of Financial Condition |  |  |  |
|  | Net Amounts of Assets Presented in the Statements of Financial Condition (A) |  |  | Financial Instruments Collateral Received (B) |  |  | Cash Collateral Received (C) |  |  | Net Amount (D)=(A)-(B)-(C) |
At March 31, 2013: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
UBS Securities |  | $ | 77,060 |  |  | $ | — |  |  | $ | — |  |  | $ | 77,060 |
At December 31, 2012: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
UBS Securities |  | $ | 739,330 |  |  | $ | — |  |  | $ | — |  |  | $ | 739,330 |

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- Definition Tabular disclosure of derivative and other financial assets that are subject to offsetting, including master netting arrangements. + References No definition available. + Details
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