Collaboration Agreements - Schedule of Significant Changes in Deferred Revenue Balances, Teva Collaboration (Details) $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($)
Teva
Disaggregation of Revenue [Line Items]
Revenue recognized that was included in deferred revenue at the beginning of the period	$ (45.9)

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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration