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Fair Value Measurements (Details Textual) - USD ($) $ in Millions | Apr. 30, 2018 | Jul. 31, 2017
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Fair Value Measurements (Textual) |  |
Fair value of investments in hedge funds | $ 4.8 | $ 8.6
Carrying value of investments | $ 3.0 | $ 10.8

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- Definition Investment in hedge funds. + References No definition available. + Details
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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 + Details
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