Document and Entity Information - USD ($)	12 Months Ended
	Oct. 02, 2015	Nov. 13, 2015	Apr. 03, 2015
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Oct. 02, 2015
Document Fiscal Year Focus	2015
FY	FY
Trading Symbol	VAR
Entity Registrant Name	VARIAN MEDICAL SYSTEMS INC
Entity Central Index Key	0000203527
Current Fiscal Year End Date	--10-02
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		96,884,737
Entity Public Float			$ 9,373,307,322