Document and Entity Information - USD ($)	12 Months Ended
	Mar. 28, 2015	Jun. 22, 2015	Sep. 28, 2013
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Mar. 28, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Entity Registrant Name	ELECTRO SCIENTIFIC INDUSTRIES INC
Entity Central Index Key	0000726514
Current Fiscal Year End Date	--03-28
Entity Well-know Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		30,757,322
Entity Public Float			$ 184,853,200