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Equity Investments (Details) - Schedule of equity investments (Parentheticals) - Common Stock Class B [Member] - shares | 6 Months Ended | 12 Months Ended
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Jan. 31, 2021 | Jul. 31, 2020
Zedge, Inc. [Member] |  |
Equity Investments (Details) - Schedule of equity investments (Parentheticals) [Line Items] |  |
Class B common stock, shares | 42,282 | 42,282
Rafael Holdings, Inc [Member] |  |
Equity Investments (Details) - Schedule of equity investments (Parentheticals) [Line Items] |  |
Class B common stock, shares | 28,320 | 27,806

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