Marketable Securities (Schedule of classified marketable securities) (Details) - USD ($)	Apr. 30, 2016	Jul. 31, 2015
Available-for-sale - Cost	$ 1,151,900	$ 1,164,472
Gross Unrealized Gains	283,743	299,752
Gross Unrealized Losses	1,951	2,720
Available-for-sale - Fair Value	1,433,692	1,461,504
Noncurrent [Member] \| Mutual Funds [Member]
Available-for-sale - Cost	475,702	719,245
Gross Unrealized Gains	$ 115,019	131,639
Gross Unrealized Losses		2,720
Available-for-sale - Fair Value	$ 590,721	848,164
Noncurrent [Member] \| Equity Securities [Member]
Available-for-sale - Cost	676,198	445,227
Gross Unrealized Gains	168,724	$ 168,113
Gross Unrealized Losses	1,951
Available-for-sale - Fair Value	$ 842,971	$ 613,340

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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