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Investment in Rafael Pharmaceuticals, Inc. (Details) - Rafael [Member] - USD ($) $ in Thousands | Jul. 31, 2017 | Jul. 31, 2016
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Schedule of consolidated balance sheets |  |
Convertible promissory note (at fair value) | $ 6,300 | $ 2,000
Warrants (at cost) | 5,400 |
Right to receive additional shares (at cost) | 400 |
Total investment in Rafael | $ 12,100 | $ 2,000

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