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Equity Investments (Details) - USD ($) $ in Thousands | Jan. 31, 2020 | Jul. 31, 2019
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Equity Securities without Readily Determinable Fair Value [Line Items] |  |
Current equity investments | $ 5,890 | $ 5,688
Noncurrent equity investments | 9,592 | 9,319
Other [Member] |  |
Equity Securities without Readily Determinable Fair Value [Line Items] |  |
Noncurrent equity investments | 225 | 225
Mutual funds [Member] |  |
Equity Securities without Readily Determinable Fair Value [Line Items] |  |
Current equity investments | 5,263 | 5,053
Hedge Funds [Member] |  |
Equity Securities without Readily Determinable Fair Value [Line Items] |  |
Noncurrent equity investments | 5,322 | 5,475
Visa Series C Preferred [Member] |  |
Equity Securities without Readily Determinable Fair Value [Line Items] |  |
Noncurrent equity investments | 4,045 | 3,619
Zedge, Inc. [Member] | Common Class B |  |
Equity Securities without Readily Determinable Fair Value [Line Items] |  |
Current equity investments | 72 | 68
Rafael Holdings, Inc [Member] | Common Class B |  |
Equity Securities without Readily Determinable Fair Value [Line Items] |  |
Current equity investments | $ 555 | $ 567

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