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Rafael Holdings, Inc. Spin-Off (Details 2) - Rafael [Member] - USD ($) $ in Thousands | Jul. 31, 2018 | Jul. 31, 2017
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Schedule of consolidated balance sheets |  |
Convertible promissory note (at fair value) |  | $ 6,300
Warrants (at cost) |  | 5,400
Right to receive additional shares (at cost) |  | 400
Total investment in Rafael Pharma |  | $ 12,100

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