Long-Term Debt - Mortgage (Schedule of long-term debt) (Details) - USD ($)	3 Months Ended
Oct. 31, 2015	Jul. 31, 2015
Debt Instrument [Line Items]
Due After One Year	$ 5,748,263	$ 5,786,525
Bond St. building, Brooklyn, NY [Member]
Debt Instrument [Line Items]
Due Within One Year	152,130	150,763
Due After One Year	$ 5,748,263	$ 5,786,525
Final Payment Date	Feb. 01, 2020
Current Annual Interest Rate	3.54%

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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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.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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- Definition

Carrying value as of the balance sheet date of all notes and loans payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

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Balance Type:	credit
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- Definition

Sum of the carrying values as of the balance sheet date of the portions of all long-term notes and loans payable due within one year or the operating cycle if longer.

+ References

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Period Type:	instant

- Details

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