Condensed Statements of Cash Flows - USD ($)		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019
Cash Flows from Operating Activities:
Net income (loss)		$ (32,807,530)	$ (14,762,809)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in short-term investments		0	295,216
Change in unrealized (gain) loss on open commodity futures contracts		(4,607,389)	(10,692,387)
(Increase) decrease in receivable from Sponsor		27,859	(5,119)
(Increase) decrease in dividends receivable		23,283	(32,515)
(Increase) decrease in interest receivable		125	4,445
(Increase) decrease in prepaid insurance	[1]	9,282	83
(Increase) decrease in ETF transaction fees receivable		350	(350)
Increase (decrease) in payable due to Broker		(429,967)	0
Increase (decrease) in Management fees payable		(59,086)	(191,837)
Increase (decrease) in professional fees payable		(302,815)	(102,419)
Increase (decrease) in brokerage commissions payable		(29,850)	0
Increase (decrease) in directors' fees payable	[1]	(9,852)	(5,166)
Increase decrease in registration fees payable		0	0
Net cash provided by (used in) operating activities		(38,185,590)	(25,492,858)
Cash Flows from Financing Activities:
Addition of shares		48,892,034	6,329,250
Redemption of shares		(79,660,461)	(207,971,777)
Net cash provided by (used in) financing activities		(30,768,427)	(201,642,527)
Net Increase (Decrease) in Cash and Cash Equivalents		(68,954,017)	(227,135,385)
Total Cash, Cash Equivalents and Equity in Trading Accounts, beginning of period		197,413,898	490,625,457
Total Cash, Cash Equivalents and Equity in Trading Accounts, end of period		128,459,881	263,490,072
United States Commodity Index Fund
Cash Flows from Operating Activities:
Net income (loss)		(35,439,060)	(14,351,596)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Change in unrealized (gain) loss on open commodity futures contracts		(3,342,751)	(9,989,137)
(Increase) decrease in dividends receivable		22,713	(32,998)
(Increase) decrease in interest receivable		0	4,224
(Increase) decrease in prepaid insurance	[1]	9,489	392
(Increase) decrease in ETF transaction fees receivable		350	(350)
Increase (decrease) in payable due to Broker		0	0
Increase (decrease) in Management fees payable		(70,365)	(189,733)
Increase (decrease) in professional fees payable		(278,961)	(105,495)
Increase (decrease) in brokerage commissions payable		(29,850)	0
Increase (decrease) in directors' fees payable	[1]	(9,990)	(5,159)
Net cash provided by (used in) operating activities		(39,138,425)	(24,669,852)
Cash Flows from Financing Activities:
Addition of shares		18,654,333	0
Redemption of shares		(67,926,335)	(197,824,091)
Net cash provided by (used in) financing activities		(49,272,002)	(197,824,091)
Net Increase (Decrease) in Cash and Cash Equivalents		(88,410,427)	(222,493,943)
Total Cash, Cash Equivalents and Equity in Trading Accounts, beginning of period		190,313,994	478,509,213
Total Cash, Cash Equivalents and Equity in Trading Accounts, end of period		101,903,567	256,015,270
United States Copper Index Fund
Cash Flows from Operating Activities:
Net income (loss)		2,631,530	(411,213)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in short-term investments		0	295,216
Change in unrealized (gain) loss on open commodity futures contracts		(1,264,638)	(703,250)
(Increase) decrease in receivable from Sponsor		27,859	(5,119)
(Increase) decrease in dividends receivable		570	483
(Increase) decrease in interest receivable		125	221
(Increase) decrease in prepaid insurance	[1]	(207)	(309)
Increase (decrease) in payable due to Broker		(429,967)
Increase (decrease) in Management fees payable		11,279	(2,104)
Increase (decrease) in professional fees payable		(23,854)	3,076
Increase (decrease) in directors' fees payable	[1]	138	(7)
Net cash provided by (used in) operating activities		952,835	(823,006)
Cash Flows from Financing Activities:
Addition of shares		30,237,701	6,328,250
Redemption of shares		(11,733,126)	(10,147,686)
Net cash provided by (used in) financing activities		18,504,575	(3,819,436)
Net Increase (Decrease) in Cash and Cash Equivalents		19,457,410	(4,642,442)
Total Cash, Cash Equivalents and Equity in Trading Accounts, beginning of period		7,098,904	12,116,244
Total Cash, Cash Equivalents and Equity in Trading Accounts, end of period		26,556,314	7,473,802
USCF Crescent Crypto Index Fund
Cash Flows from Financing Activities:
Addition of shares		0	1,000
Redemption of shares		(1,000)	0
Net cash provided by (used in) financing activities	[2]	(1,000)	1,000
Net Increase (Decrease) in Cash and Cash Equivalents		(1,000)	1,000
Total Cash, Cash Equivalents and Equity in Trading Accounts, beginning of period		1,000	0
Total Cash, Cash Equivalents and Equity in Trading Accounts, end of period		0	1,000
United States Commodity Index Funds Trust
Cash Flows from Operating Activities:
Net income (loss)		$ (32,807,530)	$ (14,762,809)

[1] Certain prior year amounts have been reclassified for consistency with the current presentation.

[2]    The Sponsor contributed $1,000