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Equity Investments (Details) - Schedule of equity investments - USD ($) $ in Thousands | Oct. 31, 2020 | Jul. 31, 2020
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Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Current equity investments | $ 21,036 | $ 5,964
Noncurrent equity investments | 9,748 | 8,833
Mutual funds [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Current equity investments | 20,427 | 5,516
Hedge funds [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Noncurrent equity investments | 3,427 | 4,783
Other [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Noncurrent equity investments | 2,225 | 225
Common Stock Class B [Member] | Zedge, Inc. [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Current equity investments | 144 | 59
Common Stock Class B [Member] | Rafael Holdings, Inc [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Current equity investments | 465 | 389
Visa Series C Preferred [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Noncurrent equity investments | 1,825 | 3,825
Visa Series A Preferred [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Noncurrent equity investments | $ 2,271 |

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