Condensed Schedule of Investments (Parenthetical) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
United States Commodity Index Fund
Interest rate		0.005%
Debt Instrument, Collateral Amount	$ 27,277,314	$ 50,852,183
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.91%, 1/02/2020
Interest rate	1.91%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.03%, 1/09/2020
Interest rate	2.03%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.75%, 1/16/2020
Interest rate	1.75%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.02%, 1/30/2020
Interest rate	2.02%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.54%, 2/20/2020
Interest rate	1.54%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.70%, 3/26/2020
Interest rate	1.70%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.64%, 4/09/2020
Interest rate	1.64%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.60%, 4/16/2020
Interest rate	1.60%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.59%, 4/30/2020
Interest rate	1.59%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.55%, 5/21/2020
Interest rate	1.55%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.53%, 6/04/2020
Interest rate	1.53%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.54%, 6/18/2020
Interest rate	1.54%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.07%, 1/03/2019
Interest rate		2.07%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.16%, 1/10/2019
Interest rate		2.16%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.18%, 1/17/2019
Interest rate		2.18%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.22%, 1/24/2019
Interest rate		2.22%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.22%, 1/31/2019
Interest rate		2.22%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.25%, 2/07/2019
Interest rate		2.25%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.28%, 2/14/2019
Interest rate		2.28%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.29%, 2/21/2019
Interest rate		2.29%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.10%, 2/28/2019
Interest rate		2.10%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.34%, 3/07/2019
Interest rate		2.34%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.12%, 3/28/2019
Interest rate		2.12%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.41%, 4/04/2019
Interest rate		2.41%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.43%, 4/11/2019
Interest rate		2.43%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.22%, 4/25/2019
Interest rate		2.22%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.46%, 5/02/2019
Interest rate		2.46%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.47%, 5/09/2019
Interest rate		2.47%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.43%, 5/23/2019
Interest rate		2.43%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.51%, 6/06/2019
Interest rate		2.51%
United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.49%, 6/27/2019
Interest rate		2.49%
United States Copper Index Fund
Debt Instrument, Collateral Amount	$ 399,050	$ 1,362,458
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.88%, 1/02/2020
Interest rate	1.88%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.03%, 1/09/2020
Interest rate	2.03%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.82%, 1/16/2020
Interest rate	1.82%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.63%, 1/23/2020
Interest rate	1.63%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.69%, 1/30/2020
Interest rate	1.69%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.67%, 2/06/2020
Interest rate	1.67%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.87%, 2/13/2020
Interest rate	1.87%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.85%, 2/20/2020
Interest rate	1.85%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.66%, 2/27/2020
Interest rate	1.66%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.80%, 3/26/2020
Interest rate	1.80%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.64%, 4/09/2020
Interest rate	1.64%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.60%, 4/16/2020
Interest rate	1.60%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.52%, 4/23/2020
Interest rate	1.52%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.59%, 4/30/2020
Interest rate	1.59%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.54%, 5/07/2020
Interest rate	1.54%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.55%, 5/14/2020
Interest rate	1.55%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.55%, 5/21/2020
Interest rate	1.55%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.58%, 5/28/2020
Interest rate	1.58%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.54%, 6/18/2020
Interest rate	1.54%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 1.76%, 1/03/2019
Interest rate		1.76%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.11%, 1/10/2019
Interest rate		2.11%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.13%, 1/17/2019
Interest rate		2.13%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.15%, 1/24/2019
Interest rate		2.15%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.14%, 1/31/2019
Interest rate		2.14%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.25%, 2/07/2019
Interest rate		2.25%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.24%, 2/14/2019
Interest rate		2.24%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.29%, 2/21/2019
Interest rate		2.29%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.01%, 2/28/2019
Interest rate		2.01%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.34%, 3/07/2019
Interest rate		2.34%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.35%, 3/21/2019
Interest rate		2.35%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.19%, 3/28/2019
Interest rate		2.19%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.40%, 4/04/2019
Interest rate		2.40%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.43%, 4/11/2019
Interest rate		2.43%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.44%, 4/18/2019
Interest rate		2.44%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.36%, 4/25/2019
Interest rate		2.36%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.46%, 5/02/2019
Interest rate		2.46%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.47%, 5/09/2019
Interest rate		2.47%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.45%, 5/23/2019
Interest rate		2.45%
United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.49%, 6/20/2019
Interest rate		2.49%
Short-Term Investments | United States Commodity Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.04%, 1/23/2020
Interest rate	2.04%
Short-Term Investments | United States Copper Index Fund | Cash Equivalents | United States Treasury Obligations | U.S. Treasury Bills 2.59%, 8/15/2019
Interest rate		2.59%