Rafael Holdings, Inc. Spin-Off (Details Textual) - USD ($) $ in Thousands, shares in Millions	3 Months Ended		9 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017	Mar. 31, 2018
Rafael Holdings, Inc. Spin-Off (Textual)
Stock-based compensation expense	$ 1,033	$ 666	$ 2,842	$ 2,793
Rafael Class B Common Stock [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Options to purchase aggregate common stock					0.6
Rafael Holdings Inc [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Stock-based compensation expense	$ 200
IDT Corporation Option Holder [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Options to purchase aggregate common stock					1.3