Marketable Securities (Schedule of classified marketable securities) (Details) - USD ($)	Jan. 31, 2022	Jul. 31, 2021
Marketable Securities [Line Items]
Fair Value	$ 3,439,727	$ 3,901,093
Noncurrent [Member]
Marketable Securities [Line Items]
Fair Value	3,439,727	3,901,093
Gross Unrealized Gains	1,323,526	1,560,263
Gross Unrealized Losses
Cost	2,116,201	2,340,830
Noncurrent [Member] \| Mutual Funds [Member]
Marketable Securities [Line Items]
Fair Value	1,427,233	1,604,841
Gross Unrealized Gains	464,715	619,972
Gross Unrealized Losses
Cost	962,518	984,869
Noncurrent [Member] \| Corporate Equity Securities [Member]
Marketable Securities [Line Items]
Fair Value	2,012,494	2,296,252
Gross Unrealized Gains	858,811	940,291
Gross Unrealized Losses
Cost	$ 1,153,683	$ 1,355,961

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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Amortized cost 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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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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