2.4.0.81105 - Disclosure - Schedule of Repurchases under Repurchase Program (Detail)truefalseIn Thousands, except Per Share data, unless otherwise specifiedfalse1falseUSDfalsefalse$eol_PE5807----1310-K0007_STD_30_20130430_0http://www.sec.gov/CIK0000707549duration2013-04-01T00:00:002013-04-30T00:00:00iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2falseUSDfalsefalse$eol_PE5807----1310-K0007_STD_91_20130630_0http://www.sec.gov/CIK0000707549duration2013-04-01T00:00:002013-06-30T00:00:00sharesStandardhttp://www.xbrl.org/2003/instanceshares0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3falseUSDfalsefalse$eol_PE5807----1310-K0007_STD_98_20130331_0http://www.sec.gov/CIK0000707549duration2012-12-24T00:00:002013-03-31T00:00:00sharesStandardhttp://www.xbrl.org/2003/instanceshares0iso4217_USD_per_sharesDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instanceshares0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4falseUSDfalsefalse$eol_PE5807----1310-K0007_STD_91_20121223_0http://www.sec.gov/CIK0000707549duration2012-09-24T00:00:002012-12-23T00:00:00sharesStandardhttp://www.xbrl.org/2003/instanceshares0iso4217_USD_per_sharesDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instanceshares0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$5falseUSDfalsefalse$eol_PE5807----1310-K0007_STD_91_20120923_0http://www.sec.gov/CIK0000707549duration2012-06-25T00:00:002012-09-23T00:00:00sharesStandardhttp://www.xbrl.org/2003/instanceshares0iso4217_USD_per_sharesDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instanceshares0iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$6falseUSDfalsefalse$eol_PE5807----1310-K0007_STD_364_20120624_0http://www.sec.gov/CIK0000707549duration2011-06-27T00:00:002012-06-24T00:00:00iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true3lrcx_StockRepurchaseProgramLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse02false4us-gaap_TreasuryStockSharesAcquiredus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse9000090falsefalsefalse3truefalsefalse53120005312falsefalsefalse4truefalsefalse1019000010190falsefalsefalse5truefalsefalse1197000011970falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesNumber of shares that have been repurchased during the period and are being held in treasury.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5
false13false4us-gaap_StockRepurchasedDuringPeriodValueus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse213903000213903USD$falsetruefalse4truefalsefalse354029000354029USD$falsetruefalse5truefalsefalse344001000344001USD$falsetruefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryEquity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3
Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644
Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30, 31
-Article 5
false24false4us-gaap_TreasuryStockAcquiredAverageCostPerShareus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse37.7337.73[1]USD$falsetruefalse4truefalsefalse34.7434.74[1]USD$falsetruefalse5truefalsefalse34.7934.79[1]USD$falsetruefalse6falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalTotal cost of shares repurchased divided by the total number of shares repurchased.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655
false35false4us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmountus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse250000000250000USD$falsetruefalse2truefalsefalse250000000250000USD$falsetruefalse3falsefalsefalse00falsefalsefalse4truefalsefalse213903000213903USD$falsetruefalse5truefalsefalse567932000567932USD$falsetruefalse6truefalsefalse911933000911933USD$falsetruefalsexbrli:monetaryItemTypemonetaryAmount remaining of a stock repurchase plan authorized by an entity's Board of Directors.No definition available.false21The fair value of Lam Research equivalent restricted stock as of the acquisition date was estimated based upon the per share price of Lam Research common stock as of June 4, 2012, and giving effect to the exchange ratio of 1.125.falseSchedule of Repurchases under Repurchase Program (Detail) (USD $)ThousandsThousandsNoRoundingUnKnowntruefalsefalseSheethttp://www.lamresearch.com/taxonomy/role/DisclosureScheduleOfRepurchasesUnderRepurchaseProgram65
