Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Summary of operating results for the business segments
Revenues	$ 165	$ 112	$ 324	$ 1,815
Loss from operations before FCC Decree and stockholder settlement	(25,786)	(2,621)	(30,063)	(3,312)
Straight Path Spectrum [Member]
Summary of operating results for the business segments
Revenues	165	112	324	217
Loss from operations before FCC Decree and stockholder settlement	(2,305)	(965)	(5,290)	(1,299)
Straight Path IP Group [Member]
Summary of operating results for the business segments
Revenues				1,598
Loss from operations before FCC Decree and stockholder settlement	(856)	(1,656)	(1,731)	(2,013)
Straight Path Ventures [Member]
Summary of operating results for the business segments
Revenues
Loss from operations before FCC Decree and stockholder settlement	$ (425)		$ (842)