v2.4.1.9

Equity Transactions Share Repurchases (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended | 34 Months Ended | 3 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 | Jun. 30, 2014 | Jun. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Mar. 31, 2011 | Jun. 30, 2012 | Mar. 31, 2009
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchased During Period, Shares |  |  |  |  |  |  |  |  |  |  |  |  | 3,554 us-gaap_StockRepurchasedDuringPeriodShares | 917 us-gaap_StockRepurchasedDuringPeriodShares | 4,838 us-gaap_StockRepurchasedDuringPeriodShares | 1,012 us-gaap_StockRepurchasedDuringPeriodShares |  |  |
Stock Repurchased During Period, Value |  |  |  |  |  |  |  |  |  |  |  |  | $ 152,625,000 us-gaap_StockRepurchasedDuringPeriodValue | $ 29,135,000 us-gaap_StockRepurchasedDuringPeriodValue | $ 152,694,000 us-gaap_StockRepurchasedDuringPeriodValue | $ 25,000,000 us-gaap_StockRepurchasedDuringPeriodValue |  |  |
Common Stock, Dividends, Per Share, Declared | $ 0.20 us-gaap_CommonStockDividendsPerShareDeclared | $ 0.20 us-gaap_CommonStockDividendsPerShareDeclared | $ 0.20 us-gaap_CommonStockDividendsPerShareDeclared | $ 0.10 us-gaap_CommonStockDividendsPerShareDeclared | $ 0.10 us-gaap_CommonStockDividendsPerShareDeclared | $ 0.10 us-gaap_CommonStockDividendsPerShareDeclared | $ 0.10 us-gaap_CommonStockDividendsPerShareDeclared | $ 0.10 us-gaap_CommonStockDividendsPerShareDeclared |  |  |  |  | $ 0.70 us-gaap_CommonStockDividendsPerShareDeclared | $ 0.40 us-gaap_CommonStockDividendsPerShareDeclared | $ 1.90 us-gaap_CommonStockDividendsPerShareDeclared |  |  |  |
Dividends, Common Stock, Cash | 7,500,000 us-gaap_DividendsCommonStockCash | 7,666,000 us-gaap_DividendsCommonStockCash | 8,033,000 us-gaap_DividendsCommonStockCash | 3,954,000 us-gaap_DividendsCommonStockCash | 4,031,000 us-gaap_DividendsCommonStockCash | 4,119,000 us-gaap_DividendsCommonStockCash | 4,118,000 us-gaap_DividendsCommonStockCash | 4,115,000 us-gaap_DividendsCommonStockCash | 11,987,000 us-gaap_DividendsCommonStockCash | 8,233,000 us-gaap_DividendsCommonStockCash | 19,653,000 us-gaap_DividendsCommonStockCash | 12,352,000 us-gaap_DividendsCommonStockCash | 27,153,000 us-gaap_DividendsCommonStockCash | 16,383,000 us-gaap_DividendsCommonStockCash |  |  |  |  |
Note Warrant [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 27,600,000 us-gaap_ProceedsFromIssuanceOfWarrants / us-gaap_DebtInstrumentAxis = us-gaap_NoteWarrantMember |  |
Note Warrant2 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,100,000 us-gaap_ProceedsFromIssuanceOfWarrants / us-gaap_DebtInstrumentAxis = idcc_NoteWarrant2Member |  |
2009 Repurchase Program [Domain] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchased During Period, Shares |  |  |  |  |  |  |  |  |  |  |  |  | 0 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2009RepurchaseProgramDomain | 0 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2009RepurchaseProgramDomain | 2,286 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2009RepurchaseProgramDomain | 1,012 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2009RepurchaseProgramDomain |  |  |
Stock Repurchased During Period, Value |  |  |  |  |  |  |  |  |  |  |  |  | 0 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2009RepurchaseProgramDomain | 0 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2009RepurchaseProgramDomain | 75,000,000 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2009RepurchaseProgramDomain | 25,000,000 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2009RepurchaseProgramDomain |  |  |
2012 Repurchase Program [Domain] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchased During Period, Shares |  |  |  |  |  |  |  |  |  |  |  |  | 0 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2012RepurchaseProgramDomain | 917 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2012RepurchaseProgramDomain | 2,552 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2012RepurchaseProgramDomain | 0 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2012RepurchaseProgramDomain |  |  |
Stock Repurchased During Period, Value |  |  |  |  |  |  |  |  |  |  |  |  | 0 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2012RepurchaseProgramDomain | 29,135,000 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2012RepurchaseProgramDomain | 77,694,000 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2012RepurchaseProgramDomain | 0 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2012RepurchaseProgramDomain |  |  |
2014 Repurchase Program [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchased During Period, Shares |  |  |  |  |  |  |  |  |  |  |  |  | 3,554 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2014RepurchaseProgramMember | 0 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2014RepurchaseProgramMember | 0 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2014RepurchaseProgramMember | 0 us-gaap_StockRepurchasedDuringPeriodShares / us-gaap_ShareRepurchaseProgramAxis = idcc_A2014RepurchaseProgramMember |  |  |
Stock Repurchased During Period, Value |  |  |  |  |  |  |  |  |  |  |  |  | 152,625,000 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2014RepurchaseProgramMember | 0 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2014RepurchaseProgramMember | 0 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2014RepurchaseProgramMember | 0 us-gaap_StockRepurchasedDuringPeriodValue / us-gaap_ShareRepurchaseProgramAxis = idcc_A2014RepurchaseProgramMember |  |  |
2012 Repurchase Program [Domain] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 200,000,000 us-gaap_StockRepurchaseProgramAuthorizedAmount1 / us-gaap_StatementClassOfStockAxis = idcc_A2012RepurchaseProgramDomain |
2009 Repurchase Program [Domain] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100,000,000 us-gaap_StockRepurchaseProgramAuthorizedAmount1 / us-gaap_StatementClassOfStockAxis = idcc_A2009RepurchaseProgramDomain
2014 Repurchase Program [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  | $ 300,000,000 us-gaap_StockRepurchaseProgramAuthorizedAmount1 / us-gaap_StatementClassOfStockAxis = idcc_A2014RepurchaseProgramMember |  |  |  |  |  | $ 300,000,000 us-gaap_StockRepurchaseProgramAuthorizedAmount1 / us-gaap_StatementClassOfStockAxis = idcc_A2014RepurchaseProgramMember |  |  |  |  |  |  |  |  |  |

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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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- Definition Amount of paid and unpaid common stock dividends declared with the form of settlement in cash. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + 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 Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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- Definition Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 + Details
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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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