Document and Entity Information - USD ($)	12 Months Ended
	Jul. 31, 2017	Oct. 10, 2017	Jan. 31, 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-K
Trading Symbol	STRP
Document Period End Date	Jul. 31, 2017
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2017
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float			$ 111,832,000
Class A Common Stock
Entity Common Stock, Shares Outstanding		787,163
Class B Common Stock
Entity Common Stock, Shares Outstanding		11,948,705