FINANCIAL INSTRUMENTS AND CREDIT RISK CONCENTRATIONS (Schedule of Fair Value of Financial Instruments) (Details) - USD ($)	Jul. 31, 2021	Jul. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Marketable securities	$ 3,901,093	$ 3,744,905
Restricted cash	882,330	1,143,666
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1,552,389	3,260,135
Marketable securities	3,901,093	3,744,905
Restricted cash	882,330	1,143,666
Mortgages and note payable	7,649,632	9,519,658
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	1,552,389	3,260,135
Marketable securities	3,901,093	3,744,905
Restricted cash	882,330	1,143,666
Mortgages and note payable	$ 8,088,201	$ 9,915,121

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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