CONTRACTS AND AGREEMENTS - Additional Information (Details) - USD ($)		4 Months Ended	9 Months Ended	12 Months Ended
	May 01, 2018	Apr. 30, 2018	Sep. 30, 2020	Dec. 31, 2019
SummerHaven Agreements | United States Commodity Index Fund
Contracts and Agreements
Fee percentage	0.06%			0.06%
Percentage of fee paid less than base fee		0.14%
Multiplier to calculate base fee		0.5
Percentage multiplied to get the calculate fee to be paid		0.06%
Annual licensing fee	$ 15,000			$ 15,000
SummerHaven Agreements | United States Copper Index Fund
Contracts and Agreements
Percentage of fee paid less than base fee		0.18%
Multiplier to calculate base fee		0.5
Percentage multiplied to get the calculate fee to be paid		0.60%
Maximum
Contracts and Agreements
Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts			$ 8
Maximum | Marketing Agent Agreement
Contracts and Agreements
Fee percentage			10.00%
Minimum
Contracts and Agreements
Commissions per round-turn trade, including applicable exchange and NFA fees for Futures Contracts and options on Futures Contracts			$ 7
Minimum | Marketing Agent Agreement
Contracts and Agreements
Fee percentage			0.04%
On each Trust Series' assets up to 3 billion | Marketing Agent Agreement
Contracts and Agreements
Fee percentage			0.06%
On each Trust Series' assets up to 3 billion | Maximum | Marketing Agent Agreement
Contracts and Agreements
Base amount for determining fee percentage			$ 3,000,000,000
On each Trust Series' assets in excess of $3 billion | Maximum | Marketing Agent Agreement
Contracts and Agreements
Base amount for determining fee percentage			$ 3,000,000,000