v2.4.1.9

Significant Agreements Significant Events (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Significant Events [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenues | $ 86,121 us-gaap_Revenues | $ 77,622 us-gaap_Revenues | $ 194,234 us-gaap_Revenues | $ 57,844 us-gaap_Revenues | $ 99,683 us-gaap_Revenues | $ 110,623 us-gaap_Revenues | $ 67,692 us-gaap_Revenues | $ 47,363 us-gaap_Revenues | $ 415,821 us-gaap_Revenues | $ 325,361 us-gaap_Revenues | $ 663,063 us-gaap_Revenues
Samsung Electronics, Ltd. [Member] |  |  |  |  |  |  |  |  |  |  |
Significant Events [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 138,000 us-gaap_Revenues / us-gaap_MajorCustomersAxis = idcc_SamsungElectronicsLtdMember |  |
Samsung Electronics, Ltd. [Member] | Past Infringement [Member] |  |  |  |  |  |  |  |  |  |  |
Significant Events [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 86,200 us-gaap_Revenues / us-gaap_MajorCustomersAxis = idcc_SamsungElectronicsLtdMember / idcc_RoyaltyRevenueAxis = idcc_PastInfringementMember |  |
Samsung Electronics, Ltd. [Member] | Recurring Revenue [Domain] |  |  |  |  |  |  |  |  |  |  |
Significant Events [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 51,800 us-gaap_Revenues / us-gaap_MajorCustomersAxis = idcc_SamsungElectronicsLtdMember / idcc_RoyaltyRevenueAxis = idcc_RecurringRevenueDomain |  |
Fujitsu and another customer [Domain] |  |  |  |  |  |  |  |  |  |  |
Significant Events [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 48,100 us-gaap_Revenues / us-gaap_MajorCustomersAxis = idcc_FujitsuandanothercustomerDomain |  |
Fujitsu and another customer [Domain] | Past Infringement [Member] |  |  |  |  |  |  |  |  |  |  |
Significant Events [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 0 us-gaap_Revenues / us-gaap_MajorCustomersAxis = idcc_FujitsuandanothercustomerDomain / idcc_RoyaltyRevenueAxis = idcc_PastInfringementMember |  |
Fujitsu and another customer [Domain] | Recurring Revenue [Domain] |  |  |  |  |  |  |  |  |  |  |
Significant Events [Abstract] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | $ 16,000 us-gaap_Revenues / us-gaap_MajorCustomersAxis = idcc_FujitsuandanothercustomerDomain / idcc_RoyaltyRevenueAxis = idcc_RecurringRevenueDomain |  |

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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). + 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 210.5-03.1) -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 1 -Article 5 + Details
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