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Fair Value Measurements (Details Textual) - USD ($) $ in Millions | Jul. 31, 2015 | Jul. 31, 2014
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Fair Value Assets Liabilities Quantitative Information [Line Items] |  |
Fair value of investments in hedge funds | $ 9.1 | $ 9.5
Carrying value of investments | 3.4 | 1.8
Long-term Investments [Member] |  |
Fair Value Assets Liabilities Quantitative Information [Line Items] |  |
Fair value of investments in hedge funds | 9.1 | 9.4
Other Current Assets [Member] |  |
Fair Value Assets Liabilities Quantitative Information [Line Items] |  |
Fair value of investments in hedge funds | $ 0.1 | $ 0.1

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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=29638263&loc=d3e39828-111592 + Details
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