Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)	3 Months Ended	12 Months Ended
Apr. 30, 2019	Jan. 31, 2019
Statement of Financial Position [Abstract]
Accounts receivable from related parties	$ 68,000	$ 79,000
Allowance for doubtful accounts receivable	$ 3,000	$ 3,000
Shares of beneficial interest, without par value
Shares of beneficial interest, authorized shares	Unlimited	Unlimited
Shares of beneficial interest, shares issued	18,608,215	18,590,215
Shares of beneficial interest, shares outstanding	9,345,560	9,360,292
Treasury stock, shares held	9,262,655	9,229,923

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

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