Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Statements of Operations [Abstract]
Revenues	$ 165	$ 112	$ 324	$ 1,815
Costs and expenses:
Direct cost of revenues	26	13	67	795
Research and development	129	374	289	374
Selling, general and administrative (related party of $205, $0, $205, and $0)	3,596	2,346	7,831	3,958
Total costs and expenses	3,751	2,733	8,187	5,127
Loss from operations before item listed below	(3,586)	(2,621)	(7,863)	(3,312)
Civil penalty - FCC decree	(15,000)		(15,000)
Stockholder settlement	(7,200)		(7,200)
Loss from operations	(25,786)	(2,621)	(30,063)	(3,312)
Other income:
Interest income	6	10	13	20
Other income		390	22	390
Total other income	6	400	35	410
Loss before income taxes	(25,780)	(2,221)	(30,028)	(2,902)
Provision for income taxes			(7)	(6)
Net loss	(25,780)	(2,221)	(30,035)	(2,908)
Net loss attributable to noncontrolling interests	355	195	479	250
Net loss attributable to Straight Path Communications Inc.	$ (25,425)	$ (2,026)	$ (29,556)	$ (2,658)
Loss per share attributable to Straight Path Communications Inc. stockholders:
Basic and diluted	$ (2.10)	$ (0.17)	$ (2.45)	$ (0.23)
Weighted-average number of shares used in calculation of loss per share:
Basic and diluted	12,132	11,854	12,075	11,832