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Fair Value Measurements (Details Textual) - USD ($) $ in Millions	Oct. 31, 2017	Jul. 31, 2017
Fair Value Measurements (Textual)
Fair value of investments in hedge funds	$ 8.6	$ 8.6
Carrying value of investments	$ 10.4	$ 10.8

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- References

No definition available.

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- Definition

Investment in hedge funds.

+ References

No definition available.

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- Definition

This item represents a financial instrument (as defined) for which it is not practicable to estimate fair value. Such disclosure may be for an individual financial instrument or a class of financial instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75030709&loc=d3e39828-111592

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