XML 42 R27.htm IDEA: XBRL DOCUMENT
v3.19.1

FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS (Additional Information) (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |
USCF Management Fee |  |  |  |  |  |  |  |  | UNL is contractually obligated to pay USCF a fee, which is paid monthly, equal to 0.75% per annum of average daily total net assets. |  |
Estimated directors fees and expenses |  |  |  |  |  |  |  |  | $ 1,447 | $ 1,929 | $ 2,888
Licensing fee incurred |  |  |  |  |  |  |  |  | 964 | 1,576 | 2,046
Expense waiver | $ (14,866) | $ (11,999) | $ (15,329) | $ (17,762) | $ (17,165) | $ (19,588) | $ (9,907) | $ (15,053) | $ 59,956 | 61,713 | 102,092
Licensing Agreements [Member] |  |  |  |  |  |  |  |  |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |
Fee percentage |  |  |  |  |  |  |  |  | 0.015% |  |
Future Period - for the year ending December 31, 2018 [Member] |  |  |  |  |  |  |  |  |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |
Estimated investor tax reporting cost |  |  |  |  |  |  |  |  | $ 65,000 | 72,000 | 76,000
Future Period - for the year ending December 31, 2018 [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |
Costs and expenses annual limit for reimbursement |  |  |  |  |  |  |  |  | 0.15% |  |
UNL [Member] | Related Public Funds [Member] |  |  |  |  |  |  |  |  |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |  |  |  |  |  |  |  |  |
Estimated directors fees and expenses |  |  |  |  |  |  |  |  | $ 1,447 | $ 1,929 | $ 2,888

X
- Definition Base Fee Percentage + References No definition available. + Details
Name: | unl_BaseFeePercentage
Namespace Prefix: | unl_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Expense Waiver + References No definition available. + Details
Name: | unl_ExpenseWaiver
Namespace Prefix: | unl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Fees Paid and Related Party Transactions [Line Items] + References No definition available. + Details
Name: | unl_FeesPaidAndRelatedPartyTransactionsLineItems
Namespace Prefix: | unl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition It represent the value of license fees and other offering expenses. + References No definition available. + Details
Name: | unl_LicenseFeesAndOtherOfferingExpenses
Namespace Prefix: | unl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percentage of Change in Costs and Expenses + References No definition available. + Details
Name: | unl_PercentageOfChangeInCostsAndExpenses
Namespace Prefix: | unl_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Description of the nature of payments to managing member or general partner for management of the day-to-day business functions of the limited liability company (LLC) or limited partnership (LP), including the fee rate, basis of calculation, relevant accounting period, whether the fee is paid to an entity other than the managing member or general partner, or whether the fee is waived. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 + Details
Name: | us-gaap_ManagementFeeDescription
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Noninterest expense related to directors' fees which are fees paid by an Entity to its directors. Directors' fees may be paid in addition to salary and other benefits. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details
Name: | us-gaap_NoninterestExpenseDirectorsFees
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of general expenses not normally included in Other Operating Costs and Expenses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.6) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
Name: | us-gaap_OtherGeneralExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=us-gaap_LicensingAgreementsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | unl_PeriodAxis=unl_FuturePeriodMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | unl_PeriodAxis=unl_UnitedStates12MonthNaturalGasFundMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=unl_RelatedPublicFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |