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Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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Equity Investments (Details) - USD ($)		3 Months Ended		6 Months Ended
Equity Investments (Details) - USD ($)	Feb. 02, 2021	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2021	Jan. 31, 2020	Dec. 07, 2020	Sep. 24, 2020	Jul. 31, 2020	Jun. 30, 2016
MarketSpark, Inc [Member] \| Subsequent Event [Member]
Equity Investments (Details) [Line Items]
Purchase paid	$ 4,000,000.0
Percentage of convertible outstanding	23.95%
Equity method investment, description	MarketSpark, which is based in San Diego, California, replaces telephone lines in commercial buildings, such as the ones used in fire panels, elevators, emergency phone lines, point-of-sale terminals, and fax lines, with cellular connections.
Rafael’s Class B Common Stock [Member]
Equity Investments (Details) [Line Items]
Owned shares (in Shares)						218,245
Number of shares purchased by warrants (in Shares)						43,649
Exercise price (in Dollars per share)						$ 22.91
Purchase price						$ 5,000,000.0
Rafael’s Class B Common Stock [Member] \| Rafael Holdings Inc [Member]
Equity Investments (Details) [Line Items]
Purchase price		$ 5,100,000		$ 5,100,000		$ 4,600,000
Purchase price per share (in Dollars per share)						$ 22.91
Rafael Warrants Class B common stock [Member] \| Rafael Holdings Inc [Member]
Equity Investments (Details) [Line Items]
Purchase price						$ 400,000
Visa Series C Convertible Participating Preferred Stock [Member]
Equity Investments (Details) [Line Items]
Owned shares (in Shares)									1,830
Convertible shares (in Shares)								13.722
Carrying value of shares increased		$ 100,000	$ 400,000		$ 400,000
Carrying value of shares decreased				$ 16,000
Visa Series A Convertible Participating Preferred Stock [Member]
Equity Investments (Details) [Line Items]
Owned shares (in Shares)							125
Convertible shares (in Shares)							6.861
Visa Series A Convertible Participating Preferred Stock [Member] \| Visa Class A Common Stock [Member]
Equity Investments (Details) [Line Items]
Owned shares (in Shares)							12,500