Collaboration Agreements - Schedule of Significant Changes in Deferred Revenue Balances, Teva Collaboration (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Disaggregation of Revenue [Line Items]
Increase as a result of cumulative-effect adjustment arising from the adoption of ASC 606	$ (29,462)	$ (59,116)
Teva \| 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
Increase due to amounts invoiced, excluding amounts recognized as revenue during the period	33,774
Revenue recognized that was included in deferred revenue at the beginning of the period	$ (67,771)

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
-Subparagraph (b)
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Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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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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