Consolidated Balance Sheets (Parenthetical) - USD ($)	12 Months Ended
Jan. 31, 2021	Jan. 31, 2020	Jul. 31, 2020
Statement of Financial Position [Abstract]
Accounts receivable from related parties		$ 375,000	$ 0
Allowance for doubtful accounts receivable		$ 15,000	$ 0
Shares of beneficial interest, without par value
Shares of beneficial interest, authorized shares	Unlimited	Unlimited
Shares of beneficial interest, shares issued		18,608,215	18,625,215
Shares of beneficial interest, shares outstanding		9,273,299	9,057,730
Treasury stock, shares held		9,334,916	9,568,485

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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