| **Fair Value Measurements (Tables)**                               | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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| **Fair Value Measurements [Abstract]**                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Assets and liabilities measured at fair value on recurring basis   | The following tables present our money market funds and contingent consideration liability measured at fair value on a recurring basis as of the dates indicated, classified by valuation hierarchy:    Fair Value Measurements at September 30, 2015   Balance atSeptember 30, 2015  Quoted Prices in Active Markets for Identical Assets(Level 1)  Significant Other Observable Inputs(Level 2)  Significant Unobservable Inputs(Level 3) Assets:        Money market funds $84,838  $84,838  $-  $- Total Assets $84,838  $84,838  $-  $-                  Liability:                Contingent consideration $18,100  $-  $-  $18,100           Total Liability $18,100  $-  $-  $18,100     Fair Value Measurements at December 31, 2014   Balance atDecember 31, 2014  Quoted Prices in Active Markets for Identical Assets(Level 1)  Significant Other Observable Inputs(Level 2)  Significant Unobservable Inputs(Level 3) Assets:        Money market funds $112,808  $112,808  $-  $- Total Assets $112,808  $112,808  $-  $-                  Liability:                Contingent consideration $17,200  $-  $-  $17,200          Total Liability $17,200  $-  $-  $17,200                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| Quantitative information for fair value measurement of Level 3     | The following table presents quantitative information pertaining to the September 30, 2015 fair value measurement of the Level 3 inputs. The first nine months of 2015 resulted in a $900 increase in the contingent consideration liability, from $17,200 to $18,100 resulting primarily from a nine month decrease in the discount period, a 0.1% increase in the risk-free rate and a 5% increase in asset volatility which affects the probability adjusted cash flow. The following additional assumptions remained unchanged since December 31, 2014:  Fair Value as of September 30, 2015  Fair Value as of December 31, 2014 Valuation TechniqueUnobservable Input Range(Weighted Average)          Contingent considerationliability:        Azedra commercialization $2,500  $2,300 Probability adjusted discounted cash flow modelProbability of success  40%             Period of milestone expected achievement  2018              Discount rate  10%               1404 commercialization $4,100  $3,800 Probability adjusted discounted cash flow modelProbability of success  59%             Period of milestone expected achievement  2019              Discount rate  10%               MIP-1095 commercialization $500  $400 Probability adjusted discounted cash flow modelProbability of success  19%             Period of milestone expected achievement  2023              Discount rate  10%               Net sales targets $11,000  $10,700 Monte-Carlo simulationProbability of success  19% - 59%(37.4%)             Period of milestone expected achievement  2019 - 2025              Discount rates (1)  12%/3.5%(1)At September 30, 2015 and December 31, 2014, net sales targets contingent consideration liability was derived from a model under a risk neutral framework resulting in the application of 12% and 3.5% discount rates to estimated cash flows. |
| Summary of activities in financial instruments with Level 3 inputs | For those financial instruments with significant Level 3 inputs, the following table summarizes the activities for the periods indicated:  Liability – Contingent ConsiderationFair Value Measurements Using SignificantUnobservable Inputs(Level 3)For the Three Months Ended September 30,   2015  2014 Description    Balance at beginning of period $18,300  $16,600 Fair value change to contingent consideration included in net (loss) income  (200)  500 Balance at end of period $18,100  $17,100   Changes in unrealized gains or losses for the period included in earnings (or changes in net assets) for liabilities held at the end of the reporting period $(200) $500   Liability – Contingent ConsiderationFair Value Measurements Using SignificantUnobservable Inputs(Level 3)For the Nine Months Ended September 30,   2015  2014 Description    Balance at beginning of period $17,200  $15,700 Fair value change to contingent consideration included in net (loss) income  900   1,400 Balance at end of period $18,100  $17,100   Changes in unrealized gains or losses for the period included in earnings (or changes in net assets) for liabilities held at the end of the reporting period $900  $1,400                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |

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| - Definition
Tabular disclosure of quantitative information about the inputs used in the fair value measurement of assets and liabilities. This disclosure may include, but is not limited to, the fair value of the asset and the liability, valuation technique used to measure fair value, the inputs used to measure fair value, the ranges of the inputs, and the weighted averages of the inputs.
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| - Definition
Tabular disclosure of assets, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, by class that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).
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| - Definition
Tabular disclosure of the fair value measurement of assets using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets) and gains or losses recognized in other comprehensive income (loss), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs), by class of asset.
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