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Equity Investments (Details) - Schedule of equity investments - USD ($) $ in Thousands | Jan. 31, 2021 | Jul. 31, 2020
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Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Current equity investments | $ 24,346 | $ 5,964
Noncurrent equity investments | 10,441 | 8,833
Fixed income mutual funds [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Current equity investments | 23,374 | 5,516
Other [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Noncurrent equity investments | 2,225 | 225
Hedge funds [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Noncurrent equity investments | 3,481 | 4,783
Rafael Holdings, Inc. warrant [Member] | Other [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Noncurrent equity investments | 380 |
Common Stock Class B [Member] | Zedge, Inc. [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Current equity investments | 307 | 59
Common Stock Class B [Member] | Rafael Holdings, Inc. warrant [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Current equity investments | 665 | 389
Visa Series C Preferred [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Noncurrent equity investments | 1,939 | 3,825
Visa Series A Preferred [Member] |  |
Equity Investments (Details) - Schedule of equity investments [Line Items] |  |
Noncurrent equity investments | $ 2,416 |

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