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Condensed Schedule of Investments (Parenthetical) | 6 Months Ended
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Jun. 30, 2017 USD ($)
Collateral Amount On Open Futures Contracts | $ 48,122,106
United States [Member] | U.S. Treasury Bills 0.62%, 7/06/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.62%
Expiration date | 7/06/2017
United States [Member] | U.S. Treasury Bills 0.59%, 7/13/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.59%
Expiration date | 7/13/2017
United States [Member] | U.S. Treasury Bills 0.61%, 7/20/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.61%
Expiration date | 7/20/2017
United States [Member] | U.S. Treasury Bills 0.60%, 7/27/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.60%
Expiration date | 7/27/2017
United States [Member] | U.S. Treasury Bills 0.61%, 8/10/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.61%
Expiration date | 8/10/2017
United States [Member] | U.S. Treasury Bills 0.65%, 8/17/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.65%
Expiration date | 8/17/2017
United States [Member] | U.S. Treasury Bills 0.67%, 8/24/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.67%
Expiration date | 8/24/2017
United States [Member] | U.S. Treasury Bills 0.76%, 8/31/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.76%
Expiration date | 8/31/2017
United States [Member] | U.S. Treasury Bills 0.84%, 9/07/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.84%
Expiration date | 9/07/2017
United States [Member] | U.S. Treasury Bills 0.87%, 9/21/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.87%
Expiration date | 9/21/2017
United States [Member] | U.S. Treasury Bills 0.89%, 9/28/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.89%
Expiration date | 9/28/2017
United States [Member] | U.S. Treasury Bills 0.90%, 10/05/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.90%
Expiration date | 10/05/2017
United States [Member] | U.S. Treasury Bills 0.92%, 10/12/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.92%
Expiration date | 10/12/2017
United States [Member] | U.S. Treasury Bills 0.91%, 10/19/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.91%
Expiration date | 10/19/2017
United States [Member] | U.S. Treasury Bills 0.95%, 10/26/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.95%
Expiration date | 10/26/2017
United States [Member] | U.S. Treasury Bills 0.97%, 11/02/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.97%
Expiration date | 11/02/2017
United States [Member] | U.S. Treasury Bills 1.01%, 11/09/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 1.01%
Expiration date | 11/09/2017
United States [Member] | U.S. Treasury Bills 0.98%, 11/16/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 0.98%
Expiration date | 11/16/2017
United States [Member] | U.S. Treasury Bills 1.05%, 11/24/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 1.05%
Expiration date | 11/24/2017
United States [Member] | U.S. Treasury Bills 1.05%, 11/30/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 1.05%
Expiration date | 11/30/2017
United States [Member] | U.S. Treasury Bills 1.08%, 12/07/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 1.08%
Expiration date | 12/07/2017
United States [Member] | U.S. Treasury Bills 1.09%, 12/14/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 1.09%
Expiration date | 12/14/2017
United States [Member] | U.S. Treasury Bills 1.11%, 12/21/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 1.11%
Expiration date | 12/21/2017
United States [Member] | U.S. Treasury Bills 1.10%, 12/28/2017 [Member] | US Treasury Securities [Member] | Cash Equivalents [Member] |
Interest rate | 1.10%
Expiration date | 12/28/2017

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