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Marketable Securities (Details Textual) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 31, 2017 | Jul. 31, 2018 | Jul. 31, 2017 | Jul. 31, 2016
Marketable Securities (Textual) |  |  |  |
Proceeds from maturities and sales of available-for-sale securities |  | $ 41,500,000 | $ 48,000,000 | $ 35,000,000
Realized gains from sales of available-for-sale securities |  |  | 300,000 | 500,000
Realized losses from sales of available-for-sale securities |  | 16,000 |  |
Unrealized losses, less than twelve months or longer |  |  |  |
Zedge [Member] |  |  |  |
Marketable Securities (Textual) |  |  |  |
Shares owned | 23,227 | 42,282 | 23,227 |
Addition received shares |  | 17,359 |  |
Shares owned fair value |  | $ 100,000 | $ 48,000 |
Payment for shares received |  | $ 100,000 |  |
Rafael Spin-Off [Member] |  |  |  |
Marketable Securities (Textual) |  |  |  |
Shares owned |  | 25,803 |  |
Shares owned fair value |  | $ 200,000 |  |
Payment for shares received |  | $ 200,000 |  |

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