v2.4.1.9

Obligations Senior Convertible Note, Note Hedge and Warrant Transaction (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified | 12 Months Ended | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Apr. 24, 2012 | Mar. 31, 2011 | Dec. 31, 2011 | Apr. 04, 2011 | Mar. 29, 2011 | Mar. 30, 2011
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes | $ 230,000,000 us-gaap_SeniorNotes | $ 230,000,000 us-gaap_SeniorNotes |  |  |  |  | $ 230,000,000 us-gaap_SeniorNotes |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  |  |  |  | 7.00%us-gaap_DebtInstrumentInterestRateEffectivePercentage |  |
Interest Expense, Debt, Excluding Amortization | 5,750,000 us-gaap_InterestExpenseDebtExcludingAmortization | 5,750,000 us-gaap_InterestExpenseDebtExcludingAmortization | 5,750,000 us-gaap_InterestExpenseDebtExcludingAmortization |  |  |  |  |  |
Accretion of debt discount | (9,022,000)us-gaap_AccretionExpense | (8,423,000)us-gaap_AccretionExpense | (7,862,000)us-gaap_AccretionExpense |  |  |  |  |  |
Amortization of Financing Costs | 1,303,000 us-gaap_AmortizationOfFinancingCosts | 1,303,000 us-gaap_AmortizationOfFinancingCosts | 1,303,000 us-gaap_AmortizationOfFinancingCosts |  |  |  |  |  |
Senior Convertible Note, Note Hedge, and Warrant Transaction Interest Expense | 16,075,000 idcc_SeniorConvertibleNoteNoteHedgeAndWarrantTransactionInterestExpense | 15,476,000 idcc_SeniorConvertibleNoteNoteHedgeAndWarrantTransactionInterestExpense | 14,915,000 idcc_SeniorConvertibleNoteNoteHedgeAndWarrantTransactionInterestExpense |  |  |  |  |  |
Convertible Note Hedge 1 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from (Payments for) Other Financing Activities |  |  |  | 37,100,000 us-gaap_ProceedsFromPaymentsForOtherFinancingActivities / us-gaap_DebtInstrumentAxis = idcc_ConvertibleNoteHedge1Member |  |  |  |  |
Convertible Note Hedge 2 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from (Payments for) Other Financing Activities |  |  |  | 5,600,000 us-gaap_ProceedsFromPaymentsForOtherFinancingActivities / us-gaap_DebtInstrumentAxis = idcc_ConvertibleNoteHedge2Member |  |  |  |  |
Convertible Note Hedge [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from (Payments for) Other Financing Activities |  |  |  | 42,700,000 us-gaap_ProceedsFromPaymentsForOtherFinancingActivities / us-gaap_DebtInstrumentAxis = idcc_ConvertibleNoteHedgeMember |  |  |  |  |
Convertible Note/ Hedge Warrant, net [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from (Payments for) Other Financing Activities |  |  | 10,900,000 us-gaap_ProceedsFromPaymentsForOtherFinancingActivities / us-gaap_DebtInstrumentAxis = idcc_ConvertibleNoteHedgeWarrantNetMember |  |  |  |  |  |
Note Warrant [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Warrants |  |  |  |  | 27,600,000 us-gaap_ProceedsFromIssuanceOfWarrants / us-gaap_DebtInstrumentAxis = us-gaap_NoteWarrantMember |  |  |  |
Note Warrant2 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Warrants |  |  |  |  | 4,100,000 us-gaap_ProceedsFromIssuanceOfWarrants / us-gaap_DebtInstrumentAxis = idcc_NoteWarrant2Member |  |  |  |
Convertible Debt [Member] | Convertible Notes 2016 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  | 2.50%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = idcc_ConvertibleNotes2016Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember |  |
Debt Instrument, Convertible, Conversion Ratio |  |  | 17.958 us-gaap_DebtInstrumentConvertibleConversionRatio1 / us-gaap_DebtInstrumentAxis = idcc_ConvertibleNotes2016Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember |  |  |  |  |  |
Debt Conversion, Converted Instrument, Amount |  |  | 1,000 us-gaap_DebtConversionConvertedInstrumentAmount1 / us-gaap_DebtInstrumentAxis = idcc_ConvertibleNotes2016Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember |  |  |  |  |  |
Debt Instrument, Convertible, Conversion Price |  |  |  |  |  |  | $ 55.69 us-gaap_DebtInstrumentConvertibleConversionPrice1 / us-gaap_DebtInstrumentAxis = idcc_ConvertibleNotes2016Member / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember |  |
Convertible Debt 1 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes |  |  |  |  |  |  |  | 200,000,000 us-gaap_SeniorNotes / us-gaap_LongtermDebtTypeAxis = idcc_ConvertibleDebt1Member |
Convertible Note Overallotment [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes |  |  |  |  |  |  |  | 30,000,000 us-gaap_SeniorNotes / us-gaap_LongtermDebtTypeAxis = idcc_ConvertibleNoteOverallotmentMember |
Equity [Member] | Convertible Debt [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Class of Warrant or Right, Outstanding |  |  |  |  |  |  |  | 3,500 us-gaap_ClassOfWarrantOrRightOutstanding / us-gaap_BalanceSheetLocationAxis = us-gaap_EquityMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember | 500 us-gaap_ClassOfWarrantOrRightOutstanding / us-gaap_BalanceSheetLocationAxis = us-gaap_EquityMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember
Derivative, Price Risk Option Strike Price |  |  |  |  |  |  |  | 64.0909 us-gaap_DerivativePriceRiskOptionStrikePrice / us-gaap_BalanceSheetLocationAxis = us-gaap_EquityMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember |
Senior Notes |  |  |  |  |  |  | 43,000,000 us-gaap_SeniorNotes / us-gaap_BalanceSheetLocationAxis = us-gaap_EquityMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember |  |
Senior Convertible Notes [Equity net of tax] |  |  |  |  |  |  | 28,000,000 idcc_SeniorConvertibleNotesEquityNetOfTax / us-gaap_BalanceSheetLocationAxis = us-gaap_EquityMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember |  |
Payments of Debt Issuance Costs |  |  |  |  |  | 1,500,000 us-gaap_PaymentsOfDebtIssuanceCosts / us-gaap_BalanceSheetLocationAxis = us-gaap_EquityMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember |  |  |
other long-term assets [Member] | Convertible Debt [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Payments of Debt Issuance Costs |  |  |  |  |  | 6,500,000 us-gaap_PaymentsOfDebtIssuanceCosts / us-gaap_BalanceSheetLocationAxis = idcc_OtherLongTermAssetsMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember |  |  |
Other Long-term Liabilities [Member] | Convertible Debt [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes |  |  |  |  |  |  | $ 187,000,000 us-gaap_SeniorNotes / us-gaap_BalanceSheetLocationAxis = idcc_OtherLongTermLiabilitiesMember / us-gaap_LongtermDebtTypeAxis = us-gaap_ConvertibleDebtMember |  |

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- Definition The component of interest expense comprised of the following: 1) Coupon Interest - interest expense charge for contractual coupon interest due on face value of the Senior Convertible Note 2) Accretion of Debt Discount - amortization of Original Issue Discount (which is charged to interest expense) on the Senior Convertible Note over the life of the Note, and 3) Amortization of Deferred Financing Costs - periodic charge against earnings over the life of the financing arrangement to which such costs relate. + References No definition available. + Details
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders. Convertible notes can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder. + References No definition available. + Details
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- Definition Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 35 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6394232&loc=d3e17558-110866 + Details
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- Definition Amount of noncash expense included in interest expense to issue debt and obtain financing associated with 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 Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 8 -Article 9 + Details
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- Definition Number of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph i -Article 4 + Details
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- Definition The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in 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 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + 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 Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + 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 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 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 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 Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 5 + Details
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- Definition The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585 + Details
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- Definition The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585 + Details
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- Definition The net cash inflow or outflow from other financing activities. This element is used when there is not a more specific and appropriate element in the taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3095-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3098-108585 + Details
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 + Details
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