Document and Entity Information	9 Months Ended
Sep. 30, 2011	Oct. 21, 2011
Entity Information [Line Items]
Entity Registrant Name	POWER INTEGRATIONS INC
Entity Central Index Key	0000833640
Trading Symbol	POWI
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2011
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		28,052,418

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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