| **Fair Value Measurements, Part 2 (Details) (USD $)In Thousands, unless otherwise specified**                                                                                                    | 12 Months Ended                                 |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------|
||
| **Total realized/unrealized gains (losses)**                                                                                                                                                     |                                            |   |   |
| Total amount of unrealized gains (losses) for the period included in other comprehensive loss attributable to the change in fair market value of related assets still held at the reporting date | $ 68                                            | $ 8 | $ 24 |
| Azedra commercialization [Member]                                                                                                                                                                |                                            |   |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Period of milestone expected achievement                                                                                                                                                         | 2017                                            |   |   |
| Fair Value                                                                                                                                                                                       | 2,300                                           |   |   |
| Valuation technique                                                                                                                                                                              | Probability adjusted discounted cash flow model |   |   |
| Discount Rate                                                                                                                                                                                    | 10.00%                                          |   |   |
| Probability of success                                                                                                                                                                           | 40.00%                                          |   |   |
| Small molecule therapeutics commercialization [Member]                                                                                                                                           |                                            |   |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Period of milestone expected achievement                                                                                                                                                         | 2021                                            |   |   |
| Fair Value                                                                                                                                                                                       | 500                                             |   |   |
| Valuation technique                                                                                                                                                                              | Probability adjusted discounted cash flow model |   |   |
| Discount Rate                                                                                                                                                                                    | 10.00%                                          |   |   |
| Probability of success                                                                                                                                                                           | 19.00%                                          |   |   |
| Net sales targets [Member]                                                                                                                                                                       |                                            |   |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Fair Value                                                                                                                                                                                       | 10,900                                          |   |   |
| Valuation technique                                                                                                                                                                              | Monte-Carlo simulation                          |   |   |
| Discount Rate                                                                                                                                                                                    | 12.50%                                          |   |   |
| Contingent Consideration Liability [Member]                                                                                                                                                      |                                            |   |   |
| **Summary of activities in financial instruments with significant Level 3 inputs [Roll Forward]**                                                                                                |                                            |   |   |
| Balance at beginning of period                                                                                                                                                                   | 0                                               | 0 |   |
| **Total realized/unrealized gains (losses)**                                                                                                                                                     |                                            |   |   |
| Fair value of contingent consideration - acquisition of Molecular Insight                                                                                                                        | 15,900                                          | 0 |   |
| Fair value adjustment to contingent consideration included in net loss                                                                                                                           | (200)                                           | 0 |   |
| Balance at end of period                                                                                                                                                                         | 15,700                                          | 0 |   |
| Changes in unrealized gains or losses for the period included in earnings (or changes in net assets) for assets or liabilities held at the end of the reporting period                           | (200)                                           | 0 |   |
| MIP - 1404 commercialization [Member]                                                                                                                                                            |                                            |   |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Period of milestone expected achievement                                                                                                                                                         | 2018                                            |   |   |
| Fair Value                                                                                                                                                                                       | 2,000                                           |   |   |
| Valuation technique                                                                                                                                                                              | Probability adjusted discounted cash flow model |   |   |
| Discount Rate                                                                                                                                                                                    | 10.00%                                          |   |   |
| Probability of success                                                                                                                                                                           | 31.00%                                          |   |   |
| Auction Rate Securities [Member]                                                                                                                                                                 |                                            |   |   |
| **Summary of activities in financial instruments with significant Level 3 inputs [Roll Forward]**                                                                                                |                                            |   |   |
| Balance at beginning of period                                                                                                                                                                   | 3,240                                           | 3,332 |   |
| Transfers into Level 3                                                                                                                                                                           | 0                                               | 0 |   |
| **Total realized/unrealized gains (losses)**                                                                                                                                                     |                                            |   |   |
| Included in net income (loss)                                                                                                                                                                    | 0                                               | 0 |   |
| Included in comprehensive income (loss)                                                                                                                                                          | 68                                              | 8 |   |
| Settlements                                                                                                                                                                                      | (1,100)                                         | (100) |   |
| Balance at end of period                                                                                                                                                                         | 2,208                                           | 3,240 |   |
| Total amount of unrealized gains (losses) for the period included in other comprehensive loss attributable to the change in fair market value of related assets still held at the reporting date | 0                                               | 0 |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Fair Value                                                                                                                                                                                       | $ 2,208                                         | $ 3,240 |   |
| Valuation technique                                                                                                                                                                              | Discounted cash flow model                      | Discounted cash flow model |   |
| Minimum [Member] | Net sales targets [Member]                                                                                                                                                    |                                            |   |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Period of milestone expected achievement                                                                                                                                                         | 2018                                            |   |   |
| Probability of success                                                                                                                                                                           | 19.00%                                          |   |   |
| Minimum [Member] | Auction Rate Securities [Member]                                                                                                                                              |                                            |   |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Redemption period                                                                                                                                                                                | 5 years                                         | 4 years |   |
| Discount Rate                                                                                                                                                                                    | 0.25%                                           | 0.125% |   |
| Maximum [Member] | Net sales targets [Member]                                                                                                                                                    |                                            |   |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Period of milestone expected achievement                                                                                                                                                         | 2022                                            |   |   |
| Probability of success                                                                                                                                                                           | 40.00%                                          |   |   |
| Maximum [Member] | Auction Rate Securities [Member]                                                                                                                                              |                                            |   |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Redemption period                                                                                                                                                                                | 15 years                                        | 15 years |   |
| Discount Rate                                                                                                                                                                                    | 3.00%                                           | 2.102% |   |
| Weighted average [Member] | Net sales targets [Member]                                                                                                                                           |                                            |   |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Probability of success                                                                                                                                                                           | 32.80%                                          |   |   |
| Weighted average [Member] | Auction Rate Securities [Member]                                                                                                                                     |                                            |   |   |
| **Fair Value Measurements, Quantitative Information**                                                                                                                                            |                                            |   |   |
| Redemption period                                                                                                                                                                                | 6 years                                         | 5 years 10 months 24 days |   |
| Discount Rate                                                                                                                                                                                    | 1.55%                                           | 0.71% |   |

| X                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value adjustment to contingent consideration included in net loss
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| - Definition
This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets) in other income. Such unrealized (holding) gains or losses relate to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).
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| - Definition
Fair value of contingent consideration - acquisition of Molecular Insight
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| X                                                                                                                                                                                                                                                            |
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| - Definition
Period of milestone expected achievement
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| - Definition
Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
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| - Definition
Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value.  For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.
+ References
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| - Definition
Percentage of likelihood a loan will not be repaid and instead default, used as an input to measure fair value.
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| - Definition
Description of the inputs and valuation technique(s) used to measure fair value.
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| - Definition
Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
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| - Definition
Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
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| - Definition
Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
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| - Definition
Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.
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| - Definition
Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
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| - Definition
Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.
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| - Definition
Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.
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