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NATURE OF BUSINESS AND ORGANIZATION (Details) | 12 Months Ended
--- | ---
Jan. 31, 2019 item shares | Jan. 31, 2018 shares | Jan. 31, 2017 shares
Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |  |  |
Period of termination of the Trust after the death of the survivor of persons named in the exhibit | 21 years |  |
Number of persons named in the exhibit to the Agreement of Trust | item | 25 |  |
Age of the youngest survivor | 54 years |  |
Number of units outstanding | 13,120,010 | 13,120,010 | 13,120,010
As Previously Reported |  |  |
Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |  |  |
Number of units outstanding |  | 13,120,010 | 13,120,010

X
- Definition Represents the number of persons named in the exhibit to the Agreement of Trust. + References No definition available. + Details
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- Definition Represents the termination period of the Trust after the death of the last survivor of the persons named in the exhibit as per the Agreement of Trust. + References No definition available. + Details
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- Definition Represents the believed age of the youngest surviving member named in the exhibit to the Agreement of Trust. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1448-109256 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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- Details
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