Condensed Schedule of Investments (Parenthetical) - USD ($)	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Collateral Amount On Open Futures Contracts		$ 4,977,658
United States \| U.S.Treasury Bills 1.19%, 4/05/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.19%
Expiration date	4/05/2018
United States \| U.S.Treasury Bills 1.22%, 4/12/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.22%
Expiration date	4/12/2018
United States \| U.S.Treasury Bills 1.23%, 4/19/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.23%
Expiration date	4/19/2018
United States \| U.S.Treasury Bills 1.25%, 4/26/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.25%
Expiration date	4/26/2018
United States \| U.S.Treasury Bills 1.27%, 5/03/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.27%
Expiration date	5/03/2018
United States \| U.S.Treasury Bills 1.32%, 5/10/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.32%
Expiration date	5/10/2018
United States \| U.S.Treasury Bills 1.37%, 5/17/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.37%
Expiration date	5/17/2018
United States \| U.S.Treasury Bills 1.43%, 5/24/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.43%
Expiration date	5/24/2018
United States \| U.S.Treasury Bills 1.43%, 5/31/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.43%
Expiration date	5/31/2018
United States \| U.S.Treasury Bills 1.45%, 6/07/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.45%
Expiration date	6/07/2018
United States \| U.S.Treasury Bills 1.46%, 6/14/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.46%
Expiration date	6/14/2018
United States \| U.S.Treasury Bills 1.49%, 6/21/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.49%
Expiration date	6/21/2018
United States \| U.S.Treasury Bills 1.50%, 6/28/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.50%
Expiration date	6/28/2018
United States \| U.S.Treasury Bills 1.56%, 7/05/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.56%
Expiration date	7/05/2018
United States \| U.S.Treasury Bills 1.56%, 7/12/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.56%
Expiration date	7/12/2018
United States \| U.S.Treasury Bills 1.60%, 7/19/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.60%
Expiration date	7/19/2018
United States \| U.S.Treasury Bills 1.61%, 7/26/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.61%
Expiration date	7/26/2018
United States \| U.S.Treasury Bills 1.63%, 8/02/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.63%
Expiration date	8/02/2018
United States \| U.S.Treasury Bills 1.71%, 8/09/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.71%
Expiration date	8/09/2018
United States \| U.S.Treasury Bills 1.77%, 8/16/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.77%
Expiration date	8/16/2018
United States \| U.S.Treasury Bills 1.82%, 8/23/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.82%
Expiration date	8/23/2018
United States \| U.S.Treasury Bills 1.82%, 8/30/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.82%
Expiration date	8/30/2018
United States \| U.S.Treasury Bills 1.85%, 9/06/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.85%
Expiration date	9/06/2018
United States \| U.S.Treasury Bills 1.90%, 9/13/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.90%
Expiration date	9/13/2018
United States \| U.S.Treasury Bills 1.92%, 9/20/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.92%
Expiration date	9/20/2018
United States \| U.S.Treasury Bills 1.90%, 9/27/2018 \| US Treasury Securities \| Cash Equivalents
Interest rate	1.90%
Expiration date	9/27/2018