2.4.0.81050 - Disclosure - Summary of Investments (Detail)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$eol_PE5807----1310-K0007_STD_0_20130630_0http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$eol_PE5807----1310-K0007_STD_0_20120624_0http://www.sec.gov/CIK0000707549instant2012-06-24T00:00:000001-01-01T00:00:00iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse02false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse13347460001334746USD$falsetruefalse2truefalsefalse12979310001297931USD$falsetruefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true23false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x711289http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCashus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse04true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse05false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse438813000438813USD$falsefalsefalse2truefalsefalse240841000240841USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false26false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse438813000438813USD$falsefalsefalse2truefalsefalse240841000240841USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true27false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse5false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x824843http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseFixed Income Money Market Fundsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldilrcx_FixedIncomeMoneyMarketFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse08true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse09false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse725311000725311USD$falsefalsefalse2truefalsefalse13188120001318812USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false210false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse725311000725311USD$falsefalsefalse2truefalsefalse13188120001318812USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true211false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse7false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x713953http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseMunicipal Notes And Bondsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MunicipalNotesMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse012true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse013false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse268390000268390USD$falsefalsefalse2truefalsefalse321001000321001USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false214false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse805000805USD$falsefalsefalse2truefalsefalse15740001574USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false215false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-449000-449USD$falsefalsefalse2truefalsefalse-8000-8USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false216false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse268746000268746USD$falsefalsefalse2truefalsefalse322567000322567USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true217false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse9false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x708214http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseUS Treasury and Agenciesus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_USTreasuryAndGovernmentMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse018true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse019false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse155648000155648USD$falsefalsefalse2truefalsefalse137516000137516USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false220false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1800018USD$falsefalsefalse2truefalsefalse4300043USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false221false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-373000-373USD$falsefalsefalse2truefalsefalse-113000-113USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false222false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse155293000155293USD$falsefalsefalse2truefalsefalse137446000137446USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true223false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse11false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x714502http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseGovernment-Sponsored Enterprisesus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_GovernmentMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse024true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse025false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse5483500054835USD$falsefalsefalse2truefalsefalse123269000123269USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false226false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse6500065USD$falsefalsefalse2truefalsefalse6700067USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false227false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-95000-95USD$falsefalsefalse2truefalsefalse-68000-68USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false228false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse5480500054805USD$falsefalsefalse2truefalsefalse123268000123268USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true229false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse13false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x738868http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseForeign Governments Bondsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldilrcx_ForeignGovernmentsMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse030true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse031false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2495000024950USD$falsefalsefalse2truefalsefalse63150006315USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false232false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse4700047USD$falsefalsefalse2truefalsefalse4300043USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false233false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-25000-25USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false234false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse2497200024972USD$falsefalsefalse2truefalsefalse63580006358USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true235false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse15false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x712150http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCorporate Notes And Bondsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CorporateBondSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse036true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse037false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse861109000861109USD$falsefalsefalse2truefalsefalse767847000767847USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false238false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse13280001328USD$falsefalsefalse2truefalsefalse14430001443USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false239false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-1945000-1945USD$falsefalsefalse2truefalsefalse-389000-389USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false240false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse860492000860492USD$falsefalsefalse2truefalsefalse768901000768901USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true241false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse17false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x707284http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseMortgage Backed Securities - Residentialus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ResidentialMortgageBackedSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse042true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse043false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2761800027618USD$falsefalsefalse2truefalsefalse2585700025857USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false244false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2900029USD$falsefalsefalse2truefalsefalse121000121USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false245false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-282000-282USD$falsefalsefalse2truefalsefalse-6000-6USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false246false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse2736500027365USD$falsefalsefalse2truefalsefalse2597200025972USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true247false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse19false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x715669http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseMortgage Backed Securities - Commercialus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CommercialMortgageBackedSecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse048true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse049false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse108204000108204USD$falsefalsefalse2truefalsefalse8468200084682USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false250false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse426000426USD$falsefalsefalse2truefalsefalse555000555USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false251false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-672000-672USD$falsefalsefalse2truefalsefalse-384000-384USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false252false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse107958000107958USD$falsefalsefalse2truefalsefalse8485300084853USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true253false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse21false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x775132http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseTotal Cash And Short Term Investmentsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldilrcx_TotalCashAndShortTermInvestmentsMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse054true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse055false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse26648780002664878USD$falsefalsefalse2truefalsefalse30261400003026140USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false256false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse27180002718USD$falsefalsefalse2truefalsefalse38460003846USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false257false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-3841000-3841USD$falsefalsefalse2truefalsefalse-968000-968USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false258false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse26637550002663755USD$falsefalsefalse2truefalsefalse30290180003029018USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true259false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse23false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x711817http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalsePublicly Traded Equity Securitiesus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_EquitySecuritiesMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse060true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse061false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse56100005610USD$falsefalsefalse2truefalsefalse93200009320USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false262false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse14860001486USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false263false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1falsefalsefalse00falsefalsefalse2truefalsefalse-3407000-3407USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false264false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse70960007096USD$falsefalsefalse2truefalsefalse59130005913USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true265false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse25false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x725570http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalsePrivate Equity Securitiesus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldilrcx_PrivateSecurityMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse066true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse067false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse50000005000USD$falsefalsefalse2truefalsefalse50000005000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false268false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse50000005000USD$falsefalsefalse2truefalsefalse50000005000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true269false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse27false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x796332http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseMutual Fundsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldilrcx_MutualFundsMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse070true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse071false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1661100016611USD$falsefalsefalse2truefalsefalse1745900017459USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false272false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse16190001619USD$falsefalsefalse2truefalsefalse366000366USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false273false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-14000-14USD$falsefalsefalse2truefalsefalse-71000-71USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false274false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse1821600018216USD$falsefalsefalse2truefalsefalse1775400017754USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true275false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse29false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x835004http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseTotal Financial Instrumentsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldilrcx_TotalFinancialInstrumentsMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse076true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse077false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse26920990002692099USD$falsefalsefalse2truefalsefalse30579190003057919USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false278false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse58230005823USD$falsefalsefalse2truefalsefalse42120004212USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false279false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-3855000-3855USD$falsefalsefalse2truefalsefalse-4446000-4446USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false280false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse26940670002694067USD$falsefalsefalse2truefalsefalse30576850003057685USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true281false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse31false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x711749http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseCash and Cash Equivalentsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashAndCashEquivalentsMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse082true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse083false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse11624730001162473USD$falsefalsefalse2truefalsefalse15647520001564752USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false284false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse11624730001162473USD$falsefalsefalse2truefalsefalse15647520001564752USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true285false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse33false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x711503http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseShort-term Investmentsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ShortTermInvestmentsMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse086true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse087false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse13358680001335868USD$falsefalsefalse2truefalsefalse12950530001295053USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false288false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse27180002718USD$falsefalsefalse2truefalsefalse38460003846USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false289false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-3841000-3841USD$falsefalsefalse2truefalsefalse-968000-968USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false290false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse13347450001334745USD$falsefalsefalse2truefalsefalse12979310001297931USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true291false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse35false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x782614http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseRestricted Cash And Investmentsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldilrcx_RestrictedCashAndInvestmentsMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse092true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse093false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse166536000166536USD$falsefalsefalse2truefalsefalse166335000166335USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false294false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse166536000166536USD$falsefalsefalse2truefalsefalse166335000166335USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true295false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse37false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x709525http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseOther Assetsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherAssetsMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse096true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse097false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2722200027222USD$falsefalsefalse2truefalsefalse3177900031779USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false298false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse31050003105USD$falsefalsefalse2truefalsefalse366000366USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false299false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-14000-14USD$falsefalsefalse2truefalsefalse-3478000-3478USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false2100false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse3031300030313USD$falsefalsefalse2truefalsefalse2866700028667USD$falsefalsefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true2101false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse39false USDtruefalse$eol_PE5807----1310-K0007_STD_0_20130630_0_710256x769126http://www.sec.gov/CIK0000707549instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseTotalus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldilrcx_TotalMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0102true 3lrcx_FinancialInstrumentsLineItemslrcx_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0103false 4lrcx_InvestmentsAmortizedCostlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse26920990002692099USD$falsefalsefalse2truefalsefalse30579190003057919USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the cost of debt and equity securities, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.No definition available.false2104false 4lrcx_InvestmentsUnrealizedGainlrcx_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse58230005823USD$falsefalsefalse2truefalsefalse42120004212USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized gain on debt or equity securities.No definition available.false2105false 4lrcx_InvestmentsUnrealizedLosslrcx_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-3855000-3855USD$falsefalsefalse2truefalsefalse-4446000-4446USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the unrealized loss on debt or equity securities.No definition available.false2106false 4us-gaap_InvestmentsFairValueDisclosureus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse26940670002694067USD$falsetruefalse2truefalsefalse30576850003057685USD$falsetruefalsexbrli:monetaryItemTypemonetaryFair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 true2falseSummary of Investments (Detail) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.lamresearch.com/taxonomy/role/DisclosureSummaryOfInvestments2106