| Collaborative and Other Agreements - Servier - Additional Information (Details) - Collaborative Arrangement [Member] - Servier [Member] € in Millions, $ in Millions | 3 Months Ended | |||
|---|---|---|---|---|
| Mar. 31, 2016  USD ($) | Mar. 31, 2016  EUR (€) | Mar. 25, 2016  USD ($) | Mar. 31, 2015  USD ($) | |
| Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] | ||||
| Future initial research and development expenses to be funded by counterparty | $ | $ 50.0 | |||
| Contract and other revenue | $ | $ 0.3 | $ 0.5 | ||
| Eligible milestone payments receivable | € 356.5 | |||
| Eligible milestone payments receivable under specific rights not met | 633.8 | |||
| Eligible milestone payments receivable, after amendment | 341.5 | |||
| Eligible milestone payments receivable under specific rights not met, after amendment | € 618.8 | |||
| Deferred revenue recognized | $ | $ 0.6 | |||
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition Amount of previously reported deferred or unearned revenue that was recognized as revenue during the period. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Contract and other revenue. No definition available. 
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- Definition Represents the eligible milestone payments receivable, if the company re-acquired cardiovascular and/or diabetes rights for use in the United States. No definition available. 
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- Definition Represents eligible milestone payments receivable after amendments, if the company re-acquired cardiovascular and/or diabetes rights for use in the United States. No definition available. 
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- Definition Represents eligible milestone payments receivable, if the company did not re-acquire those rights. No definition available. 
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- Definition Represents Eligible milestone payments receivable, if the company did not re-acquire those rights after amendment. No definition available. 
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- Definition The aggregate amount of future initial clinical research and development expenses that will be funded by the counterparty. No definition available. 
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- Details 
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- Details 
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