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Equity Investments (Details) - USD ($) | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Oct. 31, 2020 | Oct. 31, 2019 | Sep. 24, 2020 | Jul. 31, 2020 | Jun. 30, 2016
Visa Series C Convertible Participating Preferred Stock [Member] |  |  |  |  |
Equity Investments (Details) [Line Items] |  |  |  |  |
Owned shares |  |  |  |  | 1,830
Convertible shares |  |  |  | 13.722 |
Carrying value of shares decreased (in Dollars) | $ 100,000 |  |  |  |
Carrying value of shares increased (in Dollars) |  | $ 18,000 |  |  |
Visa Series A Convertible Participating Preferred Stock [Member] |  |  |  |  |
Equity Investments (Details) [Line Items] |  |  |  |  |
Owned shares |  |  | 125 |  |
Convertible shares |  |  | 6.861 |  |
Visa Series A Convertible Participating Preferred Stock [Member] | Visa Class A Common Stock [Member] |  |  |  |  |
Equity Investments (Details) [Line Items] |  |  |  |  |
Owned shares |  |  | 12,500 |  |

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