Document and Entity Information - shares	3 Months Ended
	Oct. 31, 2017	Nov. 30, 2017
Document and Entity Information
Entity Registrant Name	CANTEL MEDICAL CORP
Entity Central Index Key	0000019446
Document Type	10-Q
Document Period End Date	Oct. 31, 2017
Amendment Flag	false
Current Fiscal Year End Date	--07-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		41,805,837
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q1