Equity Investments (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Oct. 31, 2018	Jul. 31, 2018
August 1, 2018 [Member]
Equity Investments (Textual)
Cumulative effect of adopting this ASU increase in equity investments	$ 1,200
Accumulated other comprehensive loss [Member] \| August 1, 2018 [Member]
Equity Investments (Textual)
Cumulative effect of adopting this ASU increase in equity investments	33,000
Accumulated deficit [Member] \| August 1, 2018 [Member]
Equity Investments (Textual)
Cumulative effect of adopting this ASU increase in equity investments	$ 1,100
Visa Series C Convertible Participating Preferred Stock [Member]
Equity Investments (Textual)
Owned shares	1,830
Shares owned fair value	$ 22,000
Convertible shares	13.952
Zedge [Member] \| Class B common stock [Member]
Equity Investments (Textual)
Owned shares	42,282	42,282
Shares owned fair value	$ 100	$ 100
Rafael [Member] \| Class B common stock [Member]
Equity Investments (Textual)
Owned shares	25,803	25,803
Shares owned fair value	$ 200	$ 200

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Number of shares issued for each share of convertible preferred stock that is converted.

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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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