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The period required for customers to pay in advance of products being shipped by the reporting entity.

No definition available.

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Data Type:	xbrli:durationItemType
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Represents the lapse period for certain consignment arrangement.

No definition available.

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Represents the percentage of revenue generated during the period.

No definition available.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Balance Type:	debit
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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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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

Name:	srt_RangeAxis=srt_MinimumMember
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Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
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Name:	srt_MajorCustomersAxis=mpwr_CertainCustomersInChinaMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_BalanceSheetLocationAxis=mpwr_AccruedLiabilitiesCurrentMember
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Data Type:	na
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Name:	srt_ProductOrServiceAxis=us-gaap_ProductMember
Namespace Prefix:
Data Type:	na
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Name:	srt_ProductOrServiceAxis=mpwr_ProductSalesThroughDistributionArrangementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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