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Marketable Securities (Schedule of classified marketable securities) (Details) - USD ($)	Oct. 31, 2016	Jul. 31, 2016
Fair Value	$ 2,002,818	$ 2,062,205
Noncurrent [Member]
Cost	1,669,267	1,661,664
Gross Unrealized Gains	335,384	401,895
Gross Unrealized Losses	1,833	1,354
Fair Value	2,002,818	2,062,205
Noncurrent [Member] | Mutual Funds [Member]
Cost	552,628	551,573
Gross Unrealized Gains	134,648	143,026
Gross Unrealized Losses
Fair Value	687,276	694,599
Noncurrent [Member] | Corporate Equity Securities [Member]
Cost	1,116,639	1,110,091
Gross Unrealized Gains	200,736	258,869
Gross Unrealized Losses	1,833	1,354
Fair Value	$ 1,315,542	$ 1,367,606

X

- Definition

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

+ References

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

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-Section 45
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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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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
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-Section 50
-Paragraph 2
-Subparagraph (c)
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+ 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)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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