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Alleged Violation of the Lanham Act [Member] Represents the alleged violation of The Lanham Act. Retained Earnings [Member] Accrued purchases of plant and equipment Represents accrued purchases of plant and equipment. lscc_IncreaseDecreaseOfOperatingLeaseLiabilities Operating lease liabilities, current and long-term portions Represents increase (decrease) of operating lease liabilities. Revenue Title of Individual [Domain] lscc_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentageOfMarketConditionAchieved Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Market Condition Achieved The percentage of market condition achieved for awards to vest under share based payment arrangement. 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Lease liabilities incurred for new lease obligations during the period Amount of increase in operating lease liability from additional liabilities incurred during the period. Other Noncurrent Liabilities [Member] Adjustments for present value and foreign currency effects Amount of adjustments for present value and foreign currency effects on right-of-use assets under operating lease. Q2 2019 Sales Plan [Member] Represents the Q2 2019 sales plan. Lease Termination and Fixed Assets [Member] Represents lease termination and fixed assets. Software Contracts and Engineering Tools [Member] Represents software contracts and termination tools. lscc_OperatingLeaseLiabilityForPreviouslyRestructuredFacilities Operating Lease Liability for Previously Restructured Facilities Amount of liability for operating lease restructured prior to new standard adoption. June 2017 Plan [Member] Represents the June 2017 plan. lscc_RevenueFromContractWithCustomerNetImpactFromReleaseOfAccrualsOffsettingByReturnMerchandiseAuthorization Revenue From Contract With Customer, Net Impact From Release Of Accruals Offsetting By Return Merchandise Authorization Represents net impact from release of accruals offsetting by return merchandise authorization for revenue from contract with customer. lscc_RevenueFromContractWithCustomerProcessingOfReturnMerchandiseAuthorizations Revenue From Contract With Customer, Processing Of Return Merchandise Authorizations Represents processing of return merchandise authorizations for revenue from contract with customer. Secured Term Loan [Member] Represents secured term loan. Credit Agreement, May 17, 2019 [Member] Represents the credit agreement entered on May 17, 2019. Other comprehensive (loss) income: Office of the Tax Commissioner, Bermuda [Member] Other [Member] Represents other. Liability for non-cancelable contracts Amount of liability for non-cancelable contracts, classified as current. Income Tax Authority, Name [Axis] Accruals for estimated future stock rotation and scrap returns Represents accrued for estimated future stock rotation and scrap returns for contract with customer liability. Income Tax Authority, Name [Domain] Revenues recorded during the period Income Tax Authority [Axis] Amortization of acquired intangible assets Represents amortization of intangible assets acquired. 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