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Condensed Schedule of Investments (Parenthetical) | 3 Months Ended
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Mar. 31, 2018 USD ($)
Collateral Amount On Open Futures Contracts | $ 64,518,650
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.22%, 4/12/2018 [Member] |
Interest rate | 1.22%
Expiration date | 4/12/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.23%, 4/19/2018 [Member] |
Interest rate | 1.23%
Expiration date | 4/19/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.25%, 4/26/2018 [Member] |
Interest rate | 1.25%
Expiration date | 4/26/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.27%, 5/03/2018 [Member] |
Interest rate | 1.27%
Expiration date | 5/03/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.32%, 5/10/2018 [Member] |
Interest rate | 1.32%
Expiration date | 5/10/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.37%, 5/17/2018 [Member] |
Interest rate | 1.37%
Expiration date | 5/17/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.43%, 5/24/2018 [Member] |
Interest rate | 1.43%
Expiration date | 5/24/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.43%, 5/31/2018 [Member] |
Interest rate | 1.43%
Expiration date | 5/31/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.45%, 6/07/2018 [Member] |
Interest rate | 1.45%
Expiration date | 6/07/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.46%, 6/14/2018 [Member] |
Interest rate | 1.46%
Expiration date | 6/14/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.49%, 6/21/2018 [Member] |
Interest rate | 1.49%
Expiration date | 6/21/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.50%, 6/28/2018 [Member] |
Interest rate | 1.50%
Expiration date | 6/28/2018
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

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