XML 65 R47.htm IDEA: XBRL DOCUMENT v2.4.1.9

Convertible Notes (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Interest expense related to notes
Amortization of discount and debt issuance costs	$ 1,559us-gaap_AmortizationOfFinancingCostsAndDiscounts	$ 6,242us-gaap_AmortizationOfFinancingCostsAndDiscounts
Interest expense	3,083us-gaap_InterestExpense	9,926us-gaap_InterestExpense
Convertible Senior Notes
Interest expense related to notes
Interest expense	1,962us-gaap_InterestExpense / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember	8,786us-gaap_InterestExpense / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember
Convertible Senior Notes | 5% Convertible Senior Notes due 2014
Interest expense related to notes
Interest	0us-gaap_InterestExpenseDebt / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember	2,156us-gaap_InterestExpenseDebt / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember
Amortization of discount and debt issuance costs	0us-gaap_AmortizationOfFinancingCostsAndDiscounts / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember	4,769us-gaap_AmortizationOfFinancingCostsAndDiscounts / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember
Convertible notes 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
Additional Effective Interest Rate	0.00%rmbs_AdditionalEffectiveInterestRate / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember	11.70%rmbs_AdditionalEffectiveInterestRate / us-gaap_DebtInstrumentAxis = rmbs_Senior5PercentConvertibleNotesDue2014Member / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember
Convertible Senior Notes | 1.125% Convertible Senior Notes due 2018
Interest expense related to notes
Interest	403us-gaap_InterestExpenseDebt / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember	388us-gaap_InterestExpenseDebt / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember
Amortization of discount and debt issuance costs	$ 1,559us-gaap_AmortizationOfFinancingCostsAndDiscounts / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember	$ 1,473us-gaap_AmortizationOfFinancingCostsAndDiscounts / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember
Convertible notes 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
Additional Effective Interest Rate	5.50%rmbs_AdditionalEffectiveInterestRate / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember	5.50%rmbs_AdditionalEffectiveInterestRate / us-gaap_DebtInstrumentAxis = rmbs_SeniorOnePointOneTwoFivePercentConvertibleNotesDueTwoThousandEighteenMember / us-gaap_LongtermDebtTypeAxis = rmbs_ConvertibleSeniorNotesMember

X

- Definition

Additional effective interest rate for the funds borrowed under the debt agreement considering original issue discount and issuance costs.

+ References

No definition available.

+ Details

Name:	rmbs_AdditionalEffectiveInterestRate
Namespace Prefix:	rmbs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Amount of noncash expense included in interest expense to allocate debt discount and premium, and the costs to issue debt and obtain financing over the related debt instruments. Alternate captions include noncash interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

Name:	us-gaap_AmortizationOfFinancingCostsAndDiscounts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- 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

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.9)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 9

-Article 9

+ Details

Name:	us-gaap_InterestExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

Name:	us-gaap_InterestExpenseAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 5

+ Details

Name:	us-gaap_InterestExpenseDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

Name:	us-gaap_LongtermDebtTypeAxis=rmbs_ConvertibleSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: