Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Oct. 31, 2017	Oct. 31, 2016
Statements of Operations [Abstract]
Revenues	$ 165	$ 159
Costs and expenses:
Direct cost of revenues	17	41
Research and development	137	160
Selling, general and administrative (related party of $21 and $128, respectively)	3,241	3,361
Total costs and expenses	3,395	3,562
Loss from operations before profit sharing settlement	(3,230)	(3,403)
Profit sharing settlement	10,000
Loss from operations	(13,230)	(3,403)
Other income (expense):
Interest expense including amortization of debt discounts	(836)
Interest income	6	7
Other income		22
Total other income (expense)	(830)	29
Loss from continuing operations before provision for income taxes	(14,060)	(3,374)
Provision for income taxes	(7)	(7)
Loss from continuing operations	(14,067)	(3,381)
Loss from discontinued operations:
Loss from discontinued operations	(1,489)	(874)
Loss attributable to noncontrolling interests	229	124
Loss from discontinued operations attributable to Straight Path Communications Inc.	(1,260)	(750)
Net loss attributable to Straight Path Communications Inc.	$ (15,327)	$ (4,131)
Loss per share attributable to Straight Path Communications Inc. stockholders:
Basic and diluted - continuing operations	$ (1.13)	$ (0.28)
Basic and diluted - discontinued operations	(0.10)	(0.06)
Basic and diluted - total	$ (1.23)	$ (0.34)
Weighted-average number of shares used in calculation of loss per share:
Basic and diluted	12,403	12,018