Marketable Securities (Schedule of classified marketable securities) (Details) (USD $)	6 Months Ended	12 Months Ended
Jan. 31, 2014	Jul. 31, 2013
Noncurrent [Member]
Available-for-sale - Cost	$ 1,102,688	$ 2,075,640
Available-for-sale - Gross Unrealized Gains	175,408	347,382
Available-for-sale - Gross Unrealized Losses	7,982	13,749
Available-for-sale - Fair Value	1,270,114	2,409,273
Mutual Funds [Member] \| Noncurrent [Member]
Available-for-sale - Cost	687,170	1,559,925
Available-for-sale - Gross Unrealized Gains	89,305	242,041
Available-for-sale - Gross Unrealized Losses	6,298	12,052
Available-for-sale - Fair Value	770,177	1,789,914
Equity Securities [Member] \| Noncurrent [Member]
Available-for-sale - Cost	415,518	515,715
Available-for-sale - Gross Unrealized Gains	86,103	105,341
Available-for-sale - Gross Unrealized Losses	1,684	1,697
Available-for-sale - Fair Value	499,937	619,359
Certificates Of Deposit [Member] \| Current [Member]
Held-to-maturity - Cost		50,326
Held-to-maturity - Gross Unrealized Gains
Held-to-maturity - Gross Unrealized Losses
Held-to-maturity		$ 50,326

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

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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

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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-Name Accounting Standards Codification

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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Amount of unrecognized gain before loss on investments in held-to-maturity securities.

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Amount of unrecognized loss before gain on investments in held-to-maturity securities. Excludes write-down for other than temporary impairment (OTTI).

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