Document and Entity Information - shares	9 Months Ended
	Apr. 30, 2017	Jun. 09, 2017
Entity Registrant Name	Straight Path Communications Inc.
Entity Central Index Key	0001574460
Amendment Flag	false
Current Fiscal Year End Date	--07-31
Document Type	10-Q
Trading Symbol	STRP
Document Period End Date	Apr. 30, 2017
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2017
Entity Filer Category	Accelerated Filer
Class A Common Stock
Entity Common Stock, Shares Outstanding		787,163
Class B Common Stock
Entity Common Stock, Shares Outstanding		11,910,896