Concentration risk percentage benchmark for total accounts receivable

No definition available.

Name:	powi_ConcentrationRiskPercentageBenchmarkForTotalAccountsReceivable
Namespace Prefix:	powi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Customer Concentration Risk Percentage Of Total Net Revenue

+ References

No definition available.

+ Details

Name:	powi_ConcentrationRiskPercentageOfNetRevenue
Namespace Prefix:	powi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Major Customers

+ References

No definition available.

+ Details

Name:	powi_NumberOfMajorCustomers
Namespace Prefix:	powi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_ConcentrationRiskLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_Revenues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_MajorCustomersAxis=powi_DistributorsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueGoodsNetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=powi_AvnetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=powi_TenCustomersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_AccountsReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CreditConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=powi_KeiKongElectronicsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

SIGNIFICANT CUSTOMERS AND GEOGRAPHIC NET REVENUES Customer and Credit Risk Concentration (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($) Customer	Sep. 30, 2017 USD ($) Customer	Sep. 30, 2018 USD ($) Customer	Sep. 30, 2017 USD ($) Customer	Dec. 31, 2017 Customer
Concentration Risk [Line Items]
NET REVENUES \| $	$ 110,085	$ 111,255	$ 322,648	$ 323,506
Distributors [Member]
Concentration Risk [Line Items]
NET REVENUES \| $	$ 83,300	$ 83,200	$ 245,400	$ 249,300
Sales Revenue, Goods, Net \| Customer Concentration Risk [Member]
Concentration Risk [Line Items]
Number of major customers	1	1	1	1
Concentration risk percentage benchmark	10.00%	10.00%	10.00%	10.00%
Sales Revenue, Goods, Net \| Customer Concentration Risk [Member] \| Avnet
Concentration Risk [Line Items]
Concentration risk, percentage of total net revenues	14.00%	15.00%	14.00%	16.00%
Sales Revenue, Goods, Net \| Customer Concentration Risk [Member] \| Ten Customers
Concentration Risk [Line Items]
Number of major customers	10	10	10	10
Concentration risk, percentage of total net revenues	56.00%	56.00%	57.00%	55.00%
Accounts Receivable \| Credit Concentration Risk [Member]
Concentration Risk [Line Items]
Number of major customers	10		10		10
Concentration risk percentage benchmark for accounts receivable (more than)	10.00%		10.00%		10.00%
Accounts Receivable \| Credit Concentration Risk [Member] \| Avnet
Concentration Risk [Line Items]
Concentration risk percentage benchmark	20.00%		20.00%		18.00%
Accounts Receivable \| Credit Concentration Risk [Member] \| Ten Customers
Concentration Risk [Line Items]
Concentration risk percentage benchmark	67.00%		67.00%		64.00%
Accounts Receivable \| Credit Concentration Risk [Member] \| Kei Kong Electronics [Member]
Concentration Risk [Line Items]
Concentration risk percentage benchmark	12.00%		12.00%