Name:	unl_AverageDailyPercentageChangeInPriceOfBenchmarkFuturesContractConsidered
Namespace Prefix:	unl_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

The per share amount of net asset value per unit.

No definition available.

Name:	unl_NetAssetValuePerUnit
Namespace Prefix:	unl_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

Represents number of shares registered in period.

No definition available.

Name:	unl_NumberOfSharesRegisteredInPeriod
Namespace Prefix:	unl_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Number of successive valuation days over which the average daily percentage change in the fund's NAV will be considered for achieving the entity's investment objective, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	unl_NumberOfSuccessiveValuationDays
Namespace Prefix:	unl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Amount of number of shares per basket.

No definition available.

Name:	unl_NumberOfUnitsPerBasket
Namespace Prefix:	unl_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	unl_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems
Namespace Prefix:	unl_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The amounts of transaction fee paid per order.

No definition available.

Name:	unl_TransactionFeePaidPerOrder
Namespace Prefix:	unl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of number of shares issued during the period.

No definition available.

Name:	unl_UnitsIssuedDuringPeriodUnitsNewIssues
Namespace Prefix:	unl_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Amount received from the issuance of new shares during the period.

No definition available.

Name:	unl_UnitsIssuedDuringPeriodValueNewIssues
Namespace Prefix:	unl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Balance held at close of period in number of contracts.

No definition available.

Name:	us-gaap_InvestmentOwnedBalanceContracts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

Date the operations of the entity commenced, in YYYY-MM-DD format.

No definition available.