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Convertible Notes (Narrative) (Details) (USD $) | 0 Months Ended | 12 Months Ended | 0 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Aug. 16, 2013 | Dec. 31, 2014 | Jun. 29, 2009 | Dec. 31, 2013 | Dec. 31, 2012 | Jul. 10, 2009
Events of default |  |  |  |  |  |
Additional paid in capital |  | $ 1,153,435,000 us-gaap_AdditionalPaidInCapitalCommonStock |  | $ 1,128,148,000 us-gaap_AdditionalPaidInCapitalCommonStock |  |
Convertible notes |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Face Value |  | 138,000,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  | 310,500,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |
Events of default |  |  |  |  |  |
Additional paid in capital |  | 93,400,000 us-gaap_AdditionalPaidInCapitalCommonStock / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  | 93,400,000 us-gaap_AdditionalPaidInCapitalCommonStock / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |
Convertible notes | 1.125% Convertible Senior Notes due 2018 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Face Value | 138,000,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember | 138,000,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  | 138,000,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |
Liability Component, Principal amount | 107,700,000 rmbs_DebtInstrumentConvertibleCarryingAmountOfTheLiabilityComponent / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Equity Component, Principal amount | 30,300,000 us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Debt discount amortization period | 5 years | 44 months |  |  |  |
Stated Interest rate (as a percent) | 1.125%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember | 1.125%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |
Debt Issuance Cost | 3,600,000 us-gaap_DebtIssuanceCosts / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Debt Issuance Cost, Convertible, Liability Component | 2,800,000 rmbs_DebtIssuanceCostConvertibleLiabilityComponent / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Debt Issuance Cost, Convertible, Equity Component | 800,000 rmbs_DebtIssuanceCostConvertibleEquityComponent / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Debt Instrument, Term | 5 years |  |  |  |  |
Conversion rate, number of shares to be issued per $1000 of principal (in shares) | 82.8329 us-gaap_DebtInstrumentConvertibleConversionRatio1 / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Principal amount of notes used as the denominator to determine number of shares converted into notes | 1,000 rmbs_DebtInstrumentPrincipalAmountDenominatorForConversionIntoCommonStock / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Initial conversion price of notes (in dollars per share) | $ 12.07 us-gaap_DebtInstrumentConvertibleConversionPrice1 / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Number of trading days within 30 consecutive trading days in which the closing price of the entity's common stock must exceed the conversion price for the notes to be redeemable, minimum | 20 days |  |  |  |  |
Number of consecutive trading days during which the closing price of the entity's common stock must exceed the conversion price for at least 20 days in order for the notes to be redeemable | 30 days |  |  |  |  |
Percentage of the closing sales price of the entity's common stock that the conversion price must exceed in order for the notes to be convertible | 130.00%rmbs_DebtInstrumentConversionObligationCommonStockClosingSalesPriceAsPercentageOfConversionPrice / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Number of business days immediately after any ten consecutive trading day period during the note measurement period | 5 days |  |  |  |  |
Number of consecutive trading days before the five business days during the debt instrument measurement period | 5 days |  |  |  |  |
Denomination of the principal amount of notes used to calculate the percent of trading price during the debt instrument measurement period | 1,000 rmbs_DebtInstrumentConversionObligationPrincipalAmountDenominationForTradingPriceCalculation / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Maximum conversion price as a percentage of closing stock price | 98.00%rmbs_DebtInstrumentConversionPriceAsPercentageOfClosingStockPriceMaximum / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Percentage of face amount of debt instrument redeemable at the company's option | 100.00%rmbs_ConvertibleDebtInstrumentCompanyRedemptionOptionPercentageOfFaceAmountRedeemable / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Events of default |  |  |  |  |  |
Period of default in payment of interest (in days) | 30 days |  |  |  |  |
Period of default to comply with other agreements (in days) | 60 days |  |  |  |  |
Minimum percentage of aggregate outstanding principal required for default event with other agreements | 25.00%rmbs_DebtInstrumentDefaultWithOtherAgreementsPercentOfPrincipalOutstandingMinimum / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Minimum principal amount of debt nonpayment required for debt default to occur | 40,000,000 rmbs_DebtInstrumentDefaultPrincipalAmountNonpaymentMinimum / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Period of nonpayment of principal amount required for debt default to occur (in days) | 30 days |  |  |  |  |
Minimum percentage of aggregate outstanding principal required for nonpayment of debt default to occur | 25.00%rmbs_DebtInstrumentDefaultForNonpaymentPercentOfPrincipalOutstandingMinimum / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Minimum percentage of aggregate outstanding principal required for immediate payment declaration to occur | 25.00%rmbs_DebtInstrumentDefaultPercentOfPrincipalOutstandingMinimumForImmediatePaymentDeclaration / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |  |  |
Convertible notes | 5% Convertible Senior Notes due 2014 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Face Value |  | 0 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember | 150,000,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember | 172,500,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  | 22,500,000 us-gaap_DebtInstrumentFaceAmount / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember
Liability Component, Principal amount |  |  | 92,400,000 rmbs_DebtInstrumentConvertibleCarryingAmountOfTheLiabilityComponent / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  | 14,300,000 rmbs_DebtInstrumentConvertibleCarryingAmountOfTheLiabilityComponent / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember
Equity Component, Principal amount |  |  | 57,600,000 us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  | 8,200,000 us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember
Debt discount amortization period |  |  | 5 years |  |  |
Stated Interest rate (as a percent) |  |  | 5.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Debt Issuance Cost |  |  | 5,100,000 us-gaap_DebtIssuanceCosts / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Debt Issuance Cost, Convertible, Liability Component |  |  | 3,200,000 rmbs_DebtIssuanceCostConvertibleLiabilityComponent / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Debt Issuance Cost, Convertible, Equity Component |  |  | 1,900,000 rmbs_DebtIssuanceCostConvertibleEquityComponent / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Debt Instrument, Term |  |  | 5 years |  |  |
Periodic interest payment |  | 4,300,000 us-gaap_InterestPaid / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  | 8,600,000 us-gaap_InterestPaid / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember | 8,600,000 us-gaap_InterestPaid / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |
Conversion rate, number of shares to be issued per $1000 of principal (in shares) |  |  | 51.8 us-gaap_DebtInstrumentConvertibleConversionRatio1 / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Principal amount of notes used as the denominator to determine number of shares converted into notes |  |  | 1,000 rmbs_DebtInstrumentPrincipalAmountDenominatorForConversionIntoCommonStock / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Initial conversion price of notes (in dollars per share) |  |  | $ 19.31 us-gaap_DebtInstrumentConvertibleConversionPrice1 / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Number of trading days within 30 consecutive trading days in which the closing price of the entity's common stock must exceed the conversion price for the notes to be redeemable, minimum |  |  | 20 days |  |  |
Number of consecutive trading days during which the closing price of the entity's common stock must exceed the conversion price for at least 20 days in order for the notes to be redeemable |  |  | 30 days |  |  |
Percentage of the closing sales price of the entity's common stock that the conversion price must exceed in order for the notes to be convertible |  |  | 130.00%rmbs_DebtInstrumentConversionObligationCommonStockClosingSalesPriceAsPercentageOfConversionPrice / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Number of business days immediately after any ten consecutive trading day period during the note measurement period |  |  | 5 days |  |  |
Number of consecutive trading days before the five business days during the debt instrument measurement period |  |  | 10 days |  |  |
Denomination of the principal amount of notes used to calculate the percent of trading price during the debt instrument measurement period |  |  | 1,000 rmbs_DebtInstrumentConversionObligationPrincipalAmountDenominationForTradingPriceCalculation / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Maximum conversion price as a percentage of closing stock price |  |  | 98.00%rmbs_DebtInstrumentConversionPriceAsPercentageOfClosingStockPriceMaximum / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Number of trading days conversion reference period |  |  | 20 days |  |  |
Number of consecutive trading days during which the closing price of the entity's common stock must exceed the conversion price for at least 20 days in order for the notes to be redeemable at the company's option |  |  | 30 days |  |  |
Percentage of face amount of debt instrument redeemable at the company's option |  |  | 100.00%rmbs_ConvertibleDebtInstrumentCompanyRedemptionOptionPercentageOfFaceAmountRedeemable / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Number of trading days within 30 consecutive trading days in which the closing price of the entity's common stock must exceed the conversion price for the notes to be redeemable at the company's option, minimum |  |  | 20 days |  |  |
Percentage of the closing sales price of the entity's common stock that the conversion price must exceed in order for the notes to be redeemable at the company's option |  |  | 130.00%rmbs_ConvertibleDebtInstrumentCompanyRedemptionOptionCommonStockClosingSalesPriceAsPercentageOfConversionPrice / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Percentage of face amount which may be redeemed by the debt holder for cash upon occurrence of a fundamental change |  |  | 100.00%rmbs_ConvertibleDebtInstrumentPercentageOfFaceAmountRedeemableIfFundamentalChange / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Maximum increase in conversion rate per $1000 principal amount upon occurrence of fundamental change |  |  | 15.5401 rmbs_DebtInstrumentAdditionalConvertibleConversionRatioMaximum / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Events of default |  |  |  |  |  |
Period of default in payment of interest (in days) |  |  | 30 days |  |  |
Period of default to comply with other agreements (in days) |  |  | 60 days |  |  |
Minimum percentage of aggregate outstanding principal required for default event with other agreements |  |  | 25.00%rmbs_DebtInstrumentDefaultWithOtherAgreementsPercentOfPrincipalOutstandingMinimum / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Minimum principal amount of debt nonpayment required for debt default to occur |  |  | 30,000,000 rmbs_DebtInstrumentDefaultPrincipalAmountNonpaymentMinimum / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Period of nonpayment of principal amount required for debt default to occur (in days) |  |  | 10 days |  |  |
Minimum percentage of aggregate outstanding principal required for nonpayment of debt default to occur |  |  | 25.00%rmbs_DebtInstrumentDefaultForNonpaymentPercentOfPrincipalOutstandingMinimum / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Minimum percentage of aggregate outstanding principal required for immediate payment declaration to occur |  |  | 25.00%rmbs_DebtInstrumentDefaultPercentOfPrincipalOutstandingMinimumForImmediatePaymentDeclaration / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleNotesPayableMember |  |  |
Convertible Senior Notes [Member] | 1.125% Convertible Senior Notes due 2018 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Stated Interest rate (as a percent) | 1.125%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember | 1.125%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember |  | 1.125%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember |  |
Convertible Senior Notes [Member] | 5% Convertible Senior Notes due 2014 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Stated Interest rate (as a percent) |  | 5.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember |  | 5.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember | 5.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember |
Events of default |  |  |  |  |  |
Repayments of Debt |  | $ 172,500,000 us-gaap_RepaymentsOfDebt / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember |  |  |  |

X
- Definition Represents the percentage of the closing sales price of the entity's common stock for at least 20 days within 30 consecutive trading days that the closing sales price of the entity's common stock must exceed the applicable conversion price in order for the debt instruments to be redeemable at the reporting entity's option. + References No definition available. + Details
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X
- Definition The minimum number of trading days within a period of 30 consecutive trading days in which the closing price of the reporting entity's common stock must exceed the applicable conversion price in order for the debt instruments to be eligible for redemption at the reporting entity's option. + References No definition available. + Details
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- Definition The consecutive number of trading days during which the closing price of the reporting entity's common stock must exceed the applicable conversion price in order for the debt instruments to be eligible for redemption at the reporting entity's option. + References No definition available. + Details
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- Definition The percentage of the face amount of the debt instrument which may be redeemed by the entity for cash at the reporting entity's option if certain conditions are met. + References No definition available. + Details
Name: | rmbs_ConvertibleDebtInstrumentCompanyRedemptionOptionPercentageOfFaceAmountRedeemable
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- Definition The percentage of the face amount of the debt instrument which may be redeemed by the debt holder for cash upon occurrence of a fundamental change. + References No definition available. + Details
Name: | rmbs_ConvertibleDebtInstrumentPercentageOfFaceAmountRedeemableIfFundamentalChange
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Data Type: | num:percentItemType
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- Definition Represents the maximum additional conversion ratio up to which the entity can increase the conversion rate, in connection with certain fundamental changes as defined in the indenture. + References No definition available. + Details
Name: | rmbs_DebtInstrumentAdditionalConvertibleConversionRatioMaximum
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- Definition Represents the percentage of the closing sales price of the entity's common stock for at least 20 days within 30 consecutive trading days that the closing sales price of the entity's common stock must exceed the applicable conversion price in order for the debt instruments to be convertible. + References No definition available. + Details
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- Definition The minimum number of trading days within a period of 30 consecutive trading days in which the closing price of the reporting entity's common stock must exceed the applicable conversion price in order for the debt instruments to be convertible. + References No definition available. + Details
Name: | rmbs_DebtInstrumentConversionObligationCommonStockClosingSalesPriceNumberOfTradingDaysMinimum
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X
- Definition Represents the number of business days immediately after any 10 consecutive trading day period during the debt instrument measurement period. + References No definition available. + Details
Name: | rmbs_DebtInstrumentConversionObligationNumberOfBusinessDaysAfterConsecutiveTradingDayPeriod
Namespace Prefix: | rmbs_
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- Definition The consecutive number of trading days during which the closing price of the reporting entity's common stock must exceed the applicable conversion price in order for the debt instruments to be convertible. + References No definition available. + Details
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- Definition Represents the number of trading days conversion reference period specified in the Indenture. + References No definition available. + Details
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- Definition Represents the number of consecutive trading days prior to the five business days during the debt instrument measurement period. + References No definition available. + Details
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Namespace Prefix: | rmbs_
Data Type: | xbrli:durationItemType
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- Definition Represents the denomination of the principal amount of debt used to calculate the percent of trading price during the debt instrument measurement period. + References No definition available. + Details
Name: | rmbs_DebtInstrumentConversionObligationPrincipalAmountDenominationForTradingPriceCalculation
Namespace Prefix: | rmbs_
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Balance Type: | credit
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X
- Definition Represents the percentage of the trading price of each debt instrument to the conversion value of the debt instrument that the trading price must be less than in order for the debt instruments to be convertible. + References No definition available. + Details
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- Definition The carrying amount of the liability component of convertible debt, which may be settled in cash upon conversion. + References No definition available. + Details
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- Definition The minimum percentage of the aggregate outstanding principal that is required for a nonpayment of debt default event to occur. + References No definition available. + Details
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- Definition The minimum percentage of the aggregate outstanding principal that is required for a declaration of immediate payment to occur. + References No definition available. + Details
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- Definition Represent the period of default in payment of any interest. + References No definition available. + Details
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- Definition The number of days of debt nonpayment for a debt default event to occur. + References No definition available. + Details
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- Definition Represent the number of days of default to comply with the other agreements, after the receipt of written notice. + References No definition available. + Details
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- Definition The minimum principal amount of debt nonpayment for a debt default event to occur. + References No definition available. + Details
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- Definition The minimum percentage of the aggregate outstanding principal that is required for a default event to occur with other agreements. + References No definition available. + Details
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- Definition The principal amount of debt used as the denominator to determine the number of shares that the debt can be converted into at the exchange rate. + References No definition available. + Details
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- Definition Debt Issuance Cost, Convertible, Equity Component + References No definition available. + Details
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- Definition Debt Issuance Cost, Convertible, Liability Component + References No definition available. + Details
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- Definition Value received from shareholders in common stock-related transactions that are in excess of par value or stated value and amounts received from other stock-related transactions. Includes only common stock transactions (excludes preferred stock transactions). May be called contributed capital, capital in excess of par, capital surplus, or paid-in capital. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.30(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031897-161870 + Details
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- Definition The price per share of the conversion feature embedded in the debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870 + Details
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- Definition Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(5)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Conversion Rate -URI http://asc.fasb.org/extlink&oid=6509012 + Details
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- Definition Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870 + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees). + References No definition available. + Details
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- Definition The amount of cash paid for interest during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585 + Details
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- Definition The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations. + References No definition available. + Details
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