XML 19 R4.htm IDEA: XBRL DOCUMENT
v3.25.3

Schedule of Investments (Unaudited) | Sep. 30, 2025 USD ($) contract | Dec. 31, 2024 USD ($) contract
--- | --- | ---
Open Commodity Futures Contracts - Long | United States Contracts |  |  |  |  |
Notional Amount |  | $ 42,433,560 | [1] | $ 49,895,245 | [2]
Number of Contracts | contract |  | 665 | [1] | 709 | [2]
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (1,594,720) | [1] | $ (478,755) | [2]
% of Partners' Capital |  | (3.91%) | [1] | (0.97%) | [2]
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL February 2025 contracts, expiring January 2025 |  |  |  |  |
Notional Amount |  |  |  | $ 4,169,970 |
Number of Contracts | contract |  |  |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  |  |  | $ 61,510 |
% of Partners' Capital |  |  |  | 0.12% |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL March 2025 contracts, expiring February 2025 |  |  |  |  |
Notional Amount |  |  |  | $ 4,264,020 |
Number of Contracts | contract |  |  |  | 60 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  |  |  | $ 10,980 |
% of Partners' Capital |  |  |  | 0.02% |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL April 2025 contracts, expiring March 2025 |  |  |  |  |
Notional Amount |  |  |  | $ 4,255,650 |
Number of Contracts | contract |  |  |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  |  |  | $ (74,910) |
% of Partners' Capital |  |  |  | (0.15%) |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL May 2025 contracts, expiring April 2025 |  |  |  |  |
Notional Amount |  |  |  | $ 4,442,450 |
Number of Contracts | contract |  |  |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  |  |  | $ (282,950) |
% of Partners' Capital |  |  |  | (0.57%) |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL June 2025 contracts, expiring May 2025 |  |  |  |  |
Notional Amount |  |  |  | $ 4,278,770 |
Number of Contracts | contract |  |  |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  |  |  | $ (138,740) |
% of Partners' Capital |  |  |  | (0.28%) |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL July 2025 contracts, expiring June 2025 |  |  |  |  |
Notional Amount |  |  |  | $ 4,167,436 |
Number of Contracts | contract |  |  |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  |  |  | $ (46,876) |
% of Partners' Capital |  |  |  | (0.09%) |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL August 2025 contracts, expiring July 2025 |  |  |  |  |
Notional Amount |  |  |  | $ 4,375,270 |
Number of Contracts | contract |  |  |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  |  |  | $ (275,360) |
% of Partners' Capital |  |  |  | (0.56%) |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL September 2025 contracts, expiring August 2025 |  |  |  |  |
Notional Amount |  |  |  | $ 4,028,480 |
Number of Contracts | contract |  |  |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  |  |  | $ 51,370 |
% of Partners' Capital |  |  |  | 0.10% |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL October 2025 contracts, expiring September 2025 |  |  |  |  |
Notional Amount |  |  |  | $ 3,870,439 |
Number of Contracts | contract |  |  |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  |  |  | $ 189,351 |
% of Partners' Capital |  |  |  | 0.38% |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL November 2025 contracts, expiring October 2025 |  |  |  |  |
Notional Amount |  | $ 3,865,570 |  | $ 4,130,860 |
Number of Contracts | contract |  | 56 |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (372,850) |  | $ (89,360) |
% of Partners' Capital |  | (0.91%) |  | (0.18%) |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL December 2025 contracts, expiring November 2025 |  |  |  |  |
Notional Amount |  | $ 3,722,780 |  | $ 4,028,520 |
Number of Contracts | contract |  | 55 |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (314,980) |  | $ (5,310) |
% of Partners' Capital |  | (0.77%) |  | (0.01%) |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL January 2026 contracts, expiring December 2025 |  |  |  |  |
Notional Amount |  | $ 3,630,650 |  | $ 3,883,380 |
Number of Contracts | contract |  | 55 |  | 59 |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (238,250) |  | $ 121,540 |
% of Partners' Capital |  | (0.58%) |  | 0.25% |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL February 2026 contracts, expiring January 2026 |  |  |  |  |
Notional Amount |  | $ 3,758,774 |  |  |
Number of Contracts | contract |  | 55 |  |  |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (377,374) |  |  |
% of Partners' Capital |  | (0.93%) |  |  |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL March 2026 contracts, expiring February 2026 |  |  |  |  |
Notional Amount |  | $ 3,650,150 |  |  |
Number of Contracts | contract |  | 55 |  |  |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (275,350) |  |  |
% of Partners' Capital |  | (0.68%) |  |  |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL April 2026 contracts, expiring March 2026 |  |  |  |  |
Notional Amount |  | $ 3,527,890 |  |  |
Number of Contracts | contract |  | 56 |  |  |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (95,650) |  |  |
% of Partners' Capital |  | (0.23%) |  |  |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL May 2026 contracts, expiring April 2026 |  |  |  |  |
Notional Amount |  | $ 3,212,196 |  |  |
Number of Contracts | contract |  | 55 |  |  |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ 157,104 |  |  |
% of Partners' Capital |  | 0.38% |  |  |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL June 2026 contracts, expiring May 2026 |  |  |  |  |
Notional Amount |  | $ 3,323,590 |  |  |
Number of Contracts | contract |  | 56 |  |  |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ 104,730 |  |  |
% of Partners' Capital |  | 0.26% |  |  |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL July 2026 contracts, expiring June 2026 |  |  |  |  |
Notional Amount |  | $ 3,451,450 |  |  |
Number of Contracts | contract |  | 56 |  |  |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (26,490) |  |  |
% of Partners' Capital |  | (0.07%) |  |  |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL August 2026 contracts, expiring July 2026 |  |  |  |  |
Notional Amount |  | $ 3,538,750 |  |  |
Number of Contracts | contract |  | 56 |  |  |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (117,150) |  |  |
% of Partners' Capital |  | (0.29%) |  |  |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL September 2026 contracts, expiring August 2026 |  |  |  |  |
Notional Amount |  | $ 3,375,070 |  |  |
Number of Contracts | contract |  | 55 |  |  |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (17,320) |  |  |
% of Partners' Capital |  | (0.04%) |  |  |
Open Commodity Futures Contracts - Long | United States Contracts | NYMEX WTI Crude Oil Futures CL October 2026 contracts, expiring September 2026 |  |  |  |  |
Notional Amount |  | $ 3,376,690 |  |  |
Number of Contracts | contract |  | 55 |  |  |
Fair Value/Unrealized Gain (Loss) on Open Commodity Contracts |  | $ (21,140) |  |  |
% of Partners' Capital |  | (0.05%) |  |  |
Cash Equivalents | United States Money Market Funds |  |  |  |  |
Market Value |  | $ 31,630,000 |  | $ 19,630,000 |
% of Partners' Capital |  | 77.48% |  | 39.72% |
Cash Equivalents | United States Money Market Funds | Dreyfus Institutional Preferred Government Money Market Fund - Institutional Shares |  |  |  |  |
Shares/Principal Amount | [3] | $ 11,000,000 |  |  |
Market Value | [3] | $ 11,000,000 |  |  |
% of Partners' Capital | [3] | 26.95% |  |  |
Cash Equivalents | United States Money Market Funds | Morgan Stanley Institutional Liquidity Funds - Government Portfolio - Institutional Shares |  |  |  |  |
Shares/Principal Amount |  | $ 20,630,000 | [3] | $ 19,630,000 | [4]
Market Value |  | $ 20,630,000 | [3] | $ 19,630,000 | [4]
% of Partners' Capital |  | 50.53% | [3] | 39.72% | [4]
[1] | Collateral amounted to $7,039,712 on open commodity futures contracts.
[2] | Collateral amounted to $18,058,747 on open commodity futures contracts.
[3] | Reflects the 7-day yield at September 30, 2025.
[4] | Reflects the 7-day yield at December 31, 2024.

X
- Definition Fair value of investment in security owned. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(11)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 55 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477439/946-210-55-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-2 Reference 11: http://www.xbrl.org/2003/role/exampleRef -Topic 946 -SubTopic 830 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479168/946-830-55-12 Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-03(d)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479886/946-10-S99-3 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(2)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(2)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12(Column C)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-1 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12(Column A)(Footnote 1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-1 Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12(Column C)(Footnote 5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-1 Reference 20: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12(Column C)(Footnote 6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-1 Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column C)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 22: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column C)(Footnote 2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 23: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column A)(Footnote 6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 24: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column A)(Footnote 7)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 25: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column C)(Footnote 9)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 26: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14(Column F)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6 Reference 27: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14(Column A)(Footnote 1)(b)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6 Reference 28: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14(Column A)(Footnote 1)(b)(5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6 Reference 29: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14(Column F)(Footnote 4)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6 Reference 30: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14(Column F)(Footnote 7)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6 + Details
Name: | us-gaap_InvestmentOwnedAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Balance held at close of period in number of contracts. + References No definition available. + Details
Name: | us-gaap_InvestmentOwnedBalanceContracts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of principal of investment owned. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 55 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477439/946-210-55-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12(Column B)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column B)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14(Column B)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6 + Details
Name: | us-gaap_InvestmentOwnedBalancePrincipalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Nominal or face amount on the investment owned. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 946 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-03(d)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479886/946-10-S99-3 + Details
Name: | us-gaap_InvestmentOwnedUnderlyingFaceAmountAtMarketValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Percentage of Partners Capital + References No definition available. + Details
Name: | usl_PercentageOfPartnersCapital
Namespace Prefix: | usl_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Unrealized gain (loss) on open commodity futures contracts. + References No definition available. + Details
Name: | usl_UnrealizedGainLossOnOpenCommodityFuturesContracts
Namespace Prefix: | usl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancialInstrumentPerformanceStatusAxis=usl_OpenFuturesContractsLongMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=country_US
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClFebruary2025ContractsExpiringJanuary2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClMarch2025ContractsExpiringFebruary2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClApril2025ContractsExpiringMarch2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClMay2025ContractsExpiringApril2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClJune2025ContractsExpiringMay2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClJuly2025ContractsExpiringJune2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClAugust2025ContractsExpiringJuly2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClSeptember2025ContractsExpiringAugust2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClOctober2025ContractsExpiringSeptember2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClNovember2025ContractsExpiringOctober2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClDecember2025ContractsExpiringNovember2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClJanuary2026ContractsExpiringDecember2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClFebruary2026ContractsExpiringJanuary2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClMarch2026ContractsExpiringFebruary2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClApril2026ContractsExpiringMarch2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClMay2026ContractsExpiringApril2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClJune2026ContractsExpiringMay2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClJuly2026ContractsExpiringJune2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClAugust2026ContractsExpiringJuly2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClSeptember2026ContractsExpiringAugust2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=usl_NymexWtiCrudeOilFuturesClOctober2026ContractsExpiringSeptember2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CashAndCashEquivalentsAxis=us-gaap_CashEquivalentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | usl_InvestmentSecondaryCategorization1Axis=us-gaap_MoneyMarketFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=usl_DreyfusInstitutionalPreferredGovernmentMoneyMarketFundInstitutionalSharesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=usl_MorganStanleyInstitutionalLiquidityFundsGovernmentPortfolioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |