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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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