Business Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Oct. 31, 2013	Oct. 31, 2012
Summary of operating results for the business segments
Revenues	$ 127	$ 468
Loss from operations	(470)	(1,474)
Straight Path Spectrum [Member]
Summary of operating results for the business segments
Revenues	107	141
Loss from operations	(60)	(36)
Straight Path IP [Member]
Summary of operating results for the business segments
Revenues	20	327
Loss from operations	$ (410)	$ (1,438)