Document and Entity Information - USD ($)	12 Months Ended
	Jul. 31, 2018	Sep. 21, 2018	Jan. 31, 2018
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Jul. 31, 2018
Current Fiscal Year End Date	--07-31
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2018
Entity Registrant Name	COMTECH TELECOMMUNICATIONS CORP /DE/
Entity Central Index Key	0000023197
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		23,853,761
Entity Public Float			$ 500,523,000
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes