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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation 12B
-Number 240
-Section 12b
-Subsection 1

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DOCUMENT AND ENTITY INFORMATION - USD ($) $ in Millions	12 Months Ended
DOCUMENT AND ENTITY INFORMATION - USD ($) $ in Millions	Sep. 29, 2018	Nov. 16, 2018	Mar. 30, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	KULICKE & SOFFA INDUSTRIES INC
Entity Central Index Key	0000056978
Current Fiscal Year End Date	--09-29
Entity Filer Category	Large Accelerated Filer
Trading Symbol	klic
Entity Common Stock, Shares Outstanding		67,171,963
Document Type	10-K
Amendment Flag	false
Document Period End Date	Sep. 29, 2018
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2018
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 1,745.4
Amendment Description