XML 29 R14.htm IDEA: XBRL DOCUMENT
v3.7.0.1

FINANCIAL HIGHLIGHTS | 12 Months Ended
--- | ---
Dec. 31, 2016
Financial Highlights [Abstract] |
Financial Highlights | NOTE 6 - FINANCIAL HIGHLIGHTS The following table presents per share performance data and other supplemental financial data for the years ended December 31, 2016, 2015 and 2014. This information has been derived from information presented in the financial statements.
|  | Year ended |  |  | Year ended |  |  | Year ended |
|  | December 31, 2016 |  |  | December 31, 2015 |  |  | December 31, 2014 |
Per Share Operating Performance: |  |  |  |  |  |  |  |  |  |  |  |
Net asset value, beginning of year |  | $ | 17.00 |  |  | $ | 26.59 |  |  | $ | 42.83 |
Total income (loss) |  |  | 3.52 |  |  |  | (9.41) |  |  |  | (15.85) |
Net expenses |  |  | (0.13) |  |  |  | (0.18) |  |  |  | (0.39) |
Net increase (decrease) in net asset value |  |  | 3.39 |  |  |  | (9.59) |  |  |  | (16.24) |
Net asset value, end of year |  | $ | 20.39 |  |  | $ | 17.00 |  |  | $ | 26.59 |
Total Return |  |  | 19.94 | % |  |  | (36.07) | % |  |  | (37.92) | %
Ratios to Average Net Assets |  |  |  |  |  |  |  |  |  |  |  |
Total income (loss) |  |  | 27.09 | % |  |  | (37.86) | % |  |  | (34.74) | %
Management fees |  |  | 0.60 | % |  |  | 0.60 | % |  |  | 0.60 | %
Expenses excluding management fees |  |  | 0.12 | % |  |  | 0.20 | % |  |  | 0.33 | %
Net income (loss) |  |  | 26.36 | % |  |  | (38.65) | % |  |  | (35.66) | %
Total returns are calculated based on the change in value during the period. An individual shareholder’s total return and ratio may vary from the above total returns and ratios based on the timing of contributions to and withdrawals from USL.

X
- Definition The entire disclosures of supplemental information, including descriptions and amounts, related to the balance sheet, income statement, and/or cash flow statement. + References No definition available. + Details
Name: | us-gaap_AdditionalFinancialInformationDisclosureTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | usl_FinancialHighlightsAbstract
Namespace Prefix: | usl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration