Concentration risk percentage benchmark for total accounts receivable

No definition available.

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- Definition

Customer Concentration Risk Percentage Of Total Net Revenue

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Number Of Major Customers

+ References

No definition available.

+ Details

Name:	powi_NumberOfMajorCustomers
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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_MajorCustomersAxis=powi_DistributorsMember
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- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueGoodsNetMember
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- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
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- Details

Name:	us-gaap_MajorCustomersAxis=powi_AvnetMember
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- Details

Name:	us-gaap_MajorCustomersAxis=powi_TenCustomersMember
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- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_AccountsReceivableMember
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Data Type:	na
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- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CreditConcentrationRiskMember
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- Details

Name:	us-gaap_MajorCustomersAxis=powi_BurnonInternationalLtd.Member
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SIGNIFICANT CUSTOMERS AND GEOGRAPHIC NET REVENUES Customer and Credit Risk Concentration (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018 USD ($) Customer	Mar. 31, 2017 USD ($) Customer	Dec. 31, 2017 Customer
Concentration Risk [Line Items]
NET REVENUES \| $	$ 103,081	$ 104,688
Distributors [Member]
Concentration Risk [Line Items]
NET REVENUES \| $	$ 79,100	$ 80,600
Sales Revenue, Goods, Net \| Customer Concentration Risk [Member]
Concentration Risk [Line Items]
Number of major customers	1	1
Concentration risk percentage benchmark	10.00%	10.00%
Sales Revenue, Goods, Net \| Customer Concentration Risk [Member] \| Avnet
Concentration Risk [Line Items]
Concentration risk, percentage of total net revenues	16.00%	17.00%
Sales Revenue, Goods, Net \| Customer Concentration Risk [Member] \| Ten Customers
Concentration Risk [Line Items]
Number of major customers	10	10
Concentration risk, percentage of total net revenues	58.00%	59.00%
Accounts Receivable [Member] \| Credit Concentration Risk [Member]
Concentration Risk [Line Items]
Number of major customers	10		10
Concentration risk percentage benchmark for accounts receivable (more than)	10.00%		10.00%
Accounts Receivable [Member] \| Credit Concentration Risk [Member] \| Avnet
Concentration Risk [Line Items]
Concentration risk percentage benchmark	20.00%		18.00%
Accounts Receivable [Member] \| Credit Concentration Risk [Member] \| ATM Electronics
Concentration Risk [Line Items]
Concentration risk percentage benchmark	10.00%
Accounts Receivable [Member] \| Credit Concentration Risk [Member] \| Ten Customers
Concentration Risk [Line Items]
Concentration risk percentage benchmark	70.00%		67.00%