Marketable Securities (Schedule of classified marketable securities) (Details) - USD ($)	Jan. 31, 2021	Jul. 31, 2020
Marketable Securities [Line Items]
Fair Value	$ 3,924,076	$ 3,744,905
Noncurrent [Member]
Marketable Securities [Line Items]
Fair Value	3,924,076	3,744,905
Gross Unrealized Gains	1,142,847	1,120,074
Gross Unrealized Losses	4,696	5,937
Cost	2,785,925	2,630,768
Noncurrent [Member] \| Mutual Funds [Member]
Marketable Securities [Line Items]
Fair Value	1,856,357	1,374,557
Gross Unrealized Gains	403,275	297,064
Gross Unrealized Losses	4,696
Cost	1,457,778	1,077,493
Noncurrent [Member] \| Corporate Equity Securities [Member]
Marketable Securities [Line Items]
Fair Value	2,067,719	2,370,348
Gross Unrealized Gains	739,572	823,010
Gross Unrealized Losses		5,937
Cost	$ 1,328,147	$ 1,553,275

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

No definition available.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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