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Condensed Schedule of Investments (Parenthetical) | 6 Months Ended
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Jun. 30, 2018 USD ($)
Collateral Amount On Open Futures Contracts | $ 30,787,364
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.56%, 7/05/2018 [Member] |
Interest rate | 1.56%
Expiration date | 7/05/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.56%, 7/12/2018 [Member] |
Interest rate | 1.56%
Expiration date | 7/12/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.77%, 8/16/2018 [Member] |
Interest rate | 1.77%
Expiration date | 8/16/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.82%, 8/23/2018 [Member] |
Interest rate | 1.82%
Expiration date | 8/23/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.85%, 9/06/2018 [Member] |
Interest rate | 1.85%
Expiration date | 9/06/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.90%, 9/27/2018 [Member] |
Interest rate | 1.90%
Expiration date | 9/27/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.90%, 10/11/2018 [Member] |
Interest rate | 1.90%
Expiration date | 10/11/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.97%, 10/18/2018 [Member] |
Interest rate | 1.97%
Expiration date | 10/18/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.00%, 10/25/2018 [Member] |
Interest rate | 2.00%
Expiration date | 10/25/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.00%, 11/01/2018 [Member] |
Interest rate | 2.00%
Expiration date | 11/01/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.03%, 11/08/2018 [Member] |
Interest rate | 2.03%
Expiration date | 11/08/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.05%, 11/15/2018 [Member] |
Interest rate | 2.05%
Expiration date | 11/15/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.07%, 11/23/2018 [Member] |
Interest rate | 2.07%
Expiration date | 11/23/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.05%, 11/29/2018 [Member] |
Interest rate | 2.05%
Expiration date | 11/29/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.09%, 12/06/2018 [Member] |
Interest rate | 2.09%
Expiration date | 12/06/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.06%, 12/13/2018 [Member] |
Interest rate | 2.06%
Expiration date | 12/13/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.09%, 12/20/2018 [Member] |
Interest rate | 2.09%
Expiration date | 12/20/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.07%, 12/27/2018 [Member] |
Interest rate | 2.07%
Expiration date | 12/27/2018

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