Document and Entity Information - USD ($)	12 Months Ended
	Jul. 31, 2019	Sep. 19, 2019	Jan. 31, 2019
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Jul. 31, 2019
Current Fiscal Year End Date	--07-31
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2019
Entity Registrant Name	COMTECH TELECOMMUNICATIONS CORP /DE/
Entity Central Index Key	0000023197
Entity Filer Category	Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		24,267,980
Entity Public Float			$ 584,329,000
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes