Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Jul. 27, 2018
Document Information [Line Items]
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)		29,220,303
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q1
Amendment Flag	false