Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2017	Apr. 30, 2016
Summary of operating results for the business segments
Revenues	$ 167	$ 219	$ 491	$ 2,034
Loss from operations before FCC Consent Decree and stockholder settlement	(4,005)	(1,902)	(34,068)	(5,214)
Straight Path Spectrum [Member]
Summary of operating results for the business segments
Revenues	167	122	491	339
Loss from operations before FCC Consent Decree and stockholder settlement	(2,683)	(1,308)	(7,973)	(2,484)
Straight Path IP Group [Member]
Summary of operating results for the business segments
Revenues		97		1,695
Loss from operations before FCC Consent Decree and stockholder settlement	(881)	(160)	(2,612)	(2,173)
Straight Path Ventures [Member]
Summary of operating results for the business segments
Revenues
Loss from operations before FCC Consent Decree and stockholder settlement	$ (441)	$ (434)	$ (1,283)	$ (557)