Leases (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020
Rafael Holdings Inc [Member]
Leases (Textual)
Lease cost	$ 500	$ 500	$ 900	$ 900
Accounting Standards Update 2016-02 [Member]
Leases (Textual)
ASU 2016-02 Adoption			$ 12,400
Israel Lease [Member]
Leases (Textual)
Lease expires					Jul. 31, 2025
Newark Lease [Member]
Leases (Textual)
Lease expires			Apr. 30, 2025