Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2019	Apr. 26, 2019
Document And Entity Information [Abstract]
Entity Registrant Name	VARONIS SYSTEMS INC
Entity Central Index Key	0001361113
Trading Symbol	vrns
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding (in shares)		30,256,905
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Entity Emerging Growth Company	false
Entity Small Business	false
Amendment Flag	false