Collaboration Agreements Schedule of Significant Changes in Deferred Revenue Balances - Teva Collaboration (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Disaggregation of Revenue [Line Items]
Increase as a result of cumulative-effect adjustment arising from the adoption of ASC 606	$ (84,238)	$ (10,655)
Teva Pharmaceuticals Collaboration Agreement [Member] \| Accounting Standards Update 2014-09
Disaggregation of Revenue [Line Items]
Increase as a result of cumulative-effect adjustment arising from the adoption of ASC 606	48,216
Revenue recognized that was included in deferred revenue at the beginning of the period	$ (52,826)

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
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Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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