Subsequent Events	3 Months Ended
Apr. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	20. SUBSEQUENT EVENTS On May 5, 2021, the Trust received $15,000 in additional interest income in cash, as a result of the Trust’s investment in UniGen. This additional amount was used to exercise 15,000 warrants for 15,000 shares of common stock in UniGen. The Trust intends to maintain its current conservative dividend policy. The Trust currently is, and has, been paying two semiannual dividends each Fiscal Year totaling $0.02 per share per Fiscal Year. In the Fiscal Years ended January 31, 2020 and 2021, the Trust paid dividends of $0.01 per share per share in each of the second and the fourth quarters. The Trust has paid dividends each Fiscal Year since its inception in 1971. The Trust will pay the scheduled semiannual $0.01 dividend payable on July 31, 2021.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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