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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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-Section 30
-Paragraph 8
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
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false23false4lrcx_BusinessAcquisitionShareExchangeRatiolrcx_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse1.1251.125USD$falsetruefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalBusiness Acquisition, Share Exchange RatioNo definition available.false34false4us-gaap_GoodwillAcquiredDuringPeriodus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse12831110001283111000falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267
false25false4us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCostsus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse3600000036000000falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.No definition available.false26false4lrcx_CostsIncludedInProFormaNetIncomelrcx_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse122000000122000000USD$falsetruefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryCosts included in pro forma net income, which are not expected to occur in future quartersNo definition available.false2falseAcquisitions - Additional Information (Detail) (USD $)NoRoundingUnKnownNoRoundingUnKnowntruefalsefalseSheethttp://www.lamresearch.com/taxonomy/role/DisclosureAcquisitionsAdditionalInformation46
