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This item represents the unrealized gain on debt or equity securities.

No definition available.

Name:	lrcx_InvestmentsUnrealizedGain
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This item represents the unrealized loss on debt or equity securities.

No definition available.

Name:	lrcx_InvestmentsUnrealizedLoss
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The fair value of cash and investments that is restricted as to withdrawal or usage, valued by the entity on a recurring basis. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits classified as long-term; that is not expected to be released from such existing restrictions within one year of the balance sheet date or operating cycle, whichever is longer. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet.

No definition available.

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This element represents investments classified as available for sale reported on the balance sheet at period end measured at fair value on a recurring basis by the entity.

No definition available.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Fair 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
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Fair value portion of other assets.

No definition available.

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