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FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS - Additional Information (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2021
Fees Paid and Related Party Transactions [Line Items] |  |  |
Percentage of management fee in average daily total net assets | 0.60% |  |
Registration fees | $ 37,350 | $ 0 |
Estimated directors' fees and expenses | 5,530 | 3,122 |
Licensing fee incurred | $ 7,845 | $ 1,707 |
Scenario Forecast |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |
Estimated directors' fees and expenses |  |  | $ 57,000
Investor tax reporting cost |  |  | 280,000
USL and the Related Public Funds, other than USCI, USAG, CPER and USMI | Scenario Forecast |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |
Estimated directors' fees and expenses |  |  | $ 1,223,400
On and after October 20, 2011 |  |  |
Fees Paid and Related Party Transactions [Line Items] |  |  |
Fee percentage | 0.015% |  |

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- 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=120399700&loc=SL114874048-224260 + Details
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- 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=120395209&loc=SL114868664-224227 + Details
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- Definition It represent the value of license fees and other offering expenses. + References No definition available. + Details
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- Definition Percentage of Management Fee In Average Daily Total Net Assets. + References No definition available. + Details
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