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FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2026 USD ($)
FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS
Directors fees and expenses	$ 38,136	$ 15,102	$ 124,430	$ 66,141
Licensing fee incurred	17,849	$ 14,054	$ 36,445	36,703
Subsequent Event
FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS
Investor tax reporting cost					$ 1,300,000
UNG
FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS
Monthly fee obligated to pay on average daily total net assets, maximum base fee 1,000,000,000 (as a percentage)			0.6
Average daily total net assets	$ 1,000,000,000		$ 1,000,000,000
Monthly fee obligated to pay on average daily total net assets (as a percentage)			0.5
UNG \| Subsequent Event \| Forecast
FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS
Directors fees and expenses					132,000
UNG and the Related Public Funds \| Subsequent Event \| Forecast
FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS
Directors fees and expenses					$ 881,000
Licensing Agreements
FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS
Fee percentage			0.015%
United States Oil Fund LP
FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS
Registration fees and offering expenses			$ 0	$ 85,562